Biochemical Nuclear Receptor Assays - Kits

LanthaScreen™ TR-FRET CAR Coactivator Assay Kit, rabbit

This kit contains Rabbit Tb-Anti-GST antibody; other kit components are the same as kit PV4836:

The LanthaScreen® TR-FRET Constitutive Androstane Receptor (CAR) Coactivator Assay provides a sensitive and robust method for highthroughput screening (HTS) of potential CAR ligands as agonists of ligand-dependent coactivator recruitment or inverse agonists of liganddependent coactivator displacement. The kit uses a terbium-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and a CAR ligand-binding domain (CAR-LBD) that is tagged with glutathione-S-transferase (GST) in a homogeneous mix-and-read assay format.

To assay:
When running the LanthaScreen® TR-FRET CAR Coactivator Assay, CAR-LBD is added to ligand test compounds followed by addition of a mixture of the fluorescein-coactivator peptide and terbium anti-GST antibody. After an incubation period at room temperature, the 520 nm/ 495 nm TR-FRET ratio is calculated and can be used to determine the EC50 from a dose response curve of the compound. Based on the biology of the CAR-coactivator peptide interaction, this ligand’s EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and either recruit or displace coactivator peptide (Figures 1 and 2).

LanthaScreen™ TR-FRET ERR gamma Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15121:

The LanthaScreen® TR-FRET Estrogen Related Receptor (ERR) gamma Coactivator Assay Kit provides a sensitive and robust method for high-throughput screening of potential ERR gamma ligands as antagonists/inverse agonists of coactivator displacement. The homogeneous mix-and-read assay format results in a ligand EC50 composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and displace coactivator peptide (Figure 1).

How it works

The LanthaScreen® TR-FRET ERR gamma Coactivator Assay Kit includes a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and a human ERR gamma ligand-binding domain (ERR gamma-LBD) that is tagged with glutathione-S-transferase (GST). To assay, ERR gamma-LBD is added to test compounds, followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-anti- GST antibody. After room temperature incubation, the TR-FRET 520:495 emission ratio is calculated and used to determine the EC50 from a dose response curve of the compound.

Contents and Storage:

The LanthaScreen® TR-FRET ERR gamma Coactivator Assay Kit contains ERR gamma-LBD (GST) protein, fluorescently labeled PGC1a coactivator peptide, Tb-anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or +4°C).

LanthaScreen™ TR-FRET Progesterone Receptor Coactivator Assay Kit

The LanthaScreen® TR-FRET Progesterone Receptor Coactivator Assay Kit provides a sensitive and robust method for high-throughput screening of potential progesterone receptor (PR) ligands as agonists or antagonists of ligand-dependent coactivator recruitment. The kit uses a PR ligand--binding domain (PR-LBD) tagged with glutathione-S-transferase (GST) (also available separately), a terbium (Tb)-labeled anti-GST antibody, and a fluorescein-labeled coactivator peptide in a homogenous mix-and-read assay format.

Agonist Mode
When using the LanthaScreen TR-FRET Progesterone Receptor Coactivator Assay in agonist mode (to identify agonist compounds), PR-LBD is added to ligand test compounds, followed by the addition of a mixture of fluorescein-labeled coactivator peptide and Tb-labeled anti-GST antibody. After an incubation period at room temperature, the TR-FRET ratio of 520/495 nm is calculated and can be used to determine the EC50 from a dose response curve of the compound. Based on the biology of the PR-coactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (see figure).

Antagonist Mode
When using the LanthaScreen™ TR-FRET Progesterone Receptor Coactivator Assay in antagonist mode (to identify antagonist compounds), PR-LBD is added to ligand test compounds followed by addition of a mixture of agonist, fluorescein-labeled coactivator peptide, and terbium-labeled anti-GST antibody (see figure). The concentration of agonist used in this mode is the EC80 concentration as determined by first running the assay in agonist mode.

LanthaScreen™ TR-FRET PXR (SXR) Competitive Binding Assay Kit, rabbit

This kit contains Rabbit Tb-Anti-GST antibody; other kit components are the same as kit PV4839:

The LanthaScreen® TR-FRET PXR (SXR) Competitive Binding Assay Kit provides a sensitive and robust method for high-throughput screening (HTS) of ligands for the pregnane X receptor (PXR), also known as the steroid and xenobiotic receptor (SXR). The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescent small-molecule PXR ligand (Fluormone™ PXR (SXR) Green), and a human PXR (SXR) ligand-binding domain that is tagged with glutathione S-transferase (GST) in a homogeneous mix-and-read assay format.

To assay:
When running the LanthaScreen® TR-FRET PXR (SXR) competitive binding assay, a Tb-labeled anti-GST antibody is used to indirectly label the receptor by binding to its GST tag. Competitive ligand binding is detected by a test compound’s ability to displace a fluorescent ligand (tracer) from the receptor, which results in a loss of FRET signal between the Tb-anti-GST antibody and the tracer (Figure 1). This type of binding assay is analogous to radioligand-based assays, except that it eliminates handling of radioactivity and enables a homogeneous, “addition-only " format.

LanthaScreen™ TR-FRET PPAR alpha Competitive Binding Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15143:

The LanthaScreen® TR-FRET PPAR alpha Competitive Binding Assay provides a sensitive and robust method for high-throughput screening (HTS) of ligands for peroxisome proliferator-activated receptor alpha (PPAR alpha). The kit uses a terbium-labeled anti-GST antibody, a fluorescent small-molecule pan-PPAR ligand (Fluormone™ Pan-PPAR Green), and a human PPAR alpha ligand-binding domain (LBD) that is tagged with glutathione S-transferase (GST), in a homogeneous mix-and-read assay format.

To assay:
When running the LanthaScreen® TR-FRET PPAR alpha Competitive Binding Assay, Fluormone™ Pan-PPAR Green is added to ligand test compounds followed by addition of a mixture of the PPAR alpha-LBD and terbium anti-GST antibody. When the Fluormone™ Pan-PPAR Green is bound to PPAR alpha, energy transfer from the terbium-labeled antibody to the tracer occurs, and a high TR-FRET ratio is observed. Competitive ligand binding to PPAR alpha is detected by a test compound’s ability to displace the tracer, which results in a loss of FRET between the antibody and the tracer. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and can be used to determine the IC50 from a dose response curve of the compound (Figure 1). This type of binding assay is analogous to radioligandbased assays, except that it eliminates handling of radioactivity and enables a homogeneous "addition-only" format.

LanthaScreen™ TR-FRET PPAR gamma Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15126:

The LanthaScreen® TR-FRET PPAR gamma Coactivator Assay Kit provides a sensitive and robust method for high-throughput screening of potential PPAR gamma ligands as agonists or antagonists of ligand-dependent coactivator recruitment. The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and a Peroxisome Proliferator Activated Receptor (PPAR) gamma ligand-binding domain (PPAR gamma-LBD) that is tagged with glutathione-S-transferase (GST), in a homogenous mix-and-read assay format.

Agonist mode
To run the LanthaScreen® TR-FRET Peroxisome Proliferator Activated gamma Receptor Coactivator Assay in agonist mode (to identify agonist compounds), PPAR gamma-LBD is added to ligand test compounds followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-anti-GST antibody. After an incubation period at room temperature, the TR-FRET 520:495 emission ratio is calculated and used to determine the EC50 from a dose response curve of the compound. Based on the biology of the PPAR gamma-coactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (Figure 1).

Antagonist mode
When the LanthaScreen® TR-FRET Peroxisome Proliferator Activated gamma Receptor Coactivator Assay is run in antagonist mode (to identify antagonist compounds), PPAR gamma-LBD is added to ligand test compounds followed by addition of a mixture of agonist, fluores-cein-coactivator peptide, and Tb-anti-GST antibody. The concentration of agonist used in this mode is the EC80 concentration as determined by first running the assay in agonist mode (Figure 2).

Contents and Storage:
The LanthaScreen® TR-FRET PPARγ Coactivator Assay Kit contains PPAR gamma-LBD (GST) protein, fluorescently labeled TRAP220/ DRIP-2 coactivator peptide, Tb-anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or +4°C).

LanthaScreen™ TR-FRET RAR alpha Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15122:

The LanthaScreen® TR-FRET Retinoic Acid Receptor (RAR) alpha Coactivator Assay Kit provides a sensitive and robust method for high-throughput screening of potential RAR alpha ligands as agonists of coactivator recruitment. The homogeneous mix-and-read assay format results in a ligand EC50 composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (Figure 1).

How it works

The LanthaScreen® TR-FRET RAR alpha Coactivator Assay Kit includes a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and a human RAR alpha ligand-binding domain (RAR alpha-LBD) that is tagged with glutathione-S-transferase (GST). To assay, RAR alpha-LBD is added to ligand test compounds, followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-anti-GST antibody. After room temperature incubation, the TR-FRET 520:495 emission ratio is calculated and used to determine the EC50 from a dose response curve of the compound.

Contents and Storage:

The LanthaScreen® TR-FRET RAR alpha Coactivator Assay Kit contains RAR alpha-LBD (GST) protein, fluorescein-labeled D22 coactivator peptide, Tb-anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or +4°C).

PolarScreen™ Progesterone Receptor Competitor Assay Kit, Green

The PolarScreen™ Progesterone Receptor Competitor Assay Kit, Green, provides a sensitive and efficient method for high-throughput, fluorescence polarization-based screening of potential progesterone receptor (PR) ligands. The kit uses insect cell-expressed, human PR ligand binding domain tagged with glutathione-S-transferase (GST) (also available separately) and a novel, high-affinity, fluorescent progesterone receptor ligand (Fluormone™ PL Green) in a homogenous, mix-and-read assay format.

This kit produces a green color read-out; a "red" kit is also available. Both kits suitably determine the IC50s of competitive compounds. Color choice depends on the spectral properties of the compounds to be screened and the available instrumentation. For additional information or assistance contact us at drugdiscoverytech@lifetech.com.

The PolarScreen Progesterone Receptor Competitor Assay is:

• Complete & ready-to-use out of the box—all reagents included, just add your test compounds
• High throughput compatible—fluorescence polarization assays in a 384-well plate
• Convenient—components available in bulk sizes for larger screening needs

How the Assay Works
An N-terminal fusion of glutathione transferase to the ligand-binding domain of the human progesterone receptor (PR-LBD(GST)) is added to a fluorescently-tagged progesterone ligand (Fluormone PL Green) in the presence of competitor test compounds in microwell plates. The presence of effective competitors prevents the formation of a PL Green/PR-LBD(GST) complex, resulting in a decrease of the polarization value. The shift in polarization value in the presence of test compounds is used to determine relative affinity of test compounds for PR-LBD(GST).

Contact us for bulk quantities or for assistance with other nuclear receptor assay needs, from assay development to library screening and beyond.

LanthaScreen™ TR-FRET Androgen Receptor Coactivator Assay Kit

The LanthaScreen® TR-FRET Androgen Receptor Coactivator Assay Kit provides a sensitive and robust method for high-throughput screening of potential androgen receptor (AR) ligands as agonists of coactivator recruitment or antagonists of agonist-dependent coactivator recruitment. In both the agonist and antagonist modes, the homogeneous mix-and-read assay uses a rat AR ligand-binding domain (AR-LBD) tagged with hexahistidine and glutathione-S-transferase (GST) (also available separately), a terbium (Tb)-labeled anti-GST antibody, and a fluorescein-labeled coactivator peptide.

Agonist Mode
When the LanthaScreen TR-FRET Androgen Receptor Coactivator Assay is run in agonist mode (to identify agonist compounds), AR-LBD is added to ligand test compounds, followed by the addition of a mixture of fluorescein-coactivator peptide and Tb-anti-GST antibody. After room temperature incubation, the TR-FRET 520:495 nm emission ratio is calculated and used to determine the EC50 from a dose response curve of the compound. This ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (see figure).

Antagonist Mode
When the LanthaScreen TR-FRET Androgen Receptor Coactivator Assay is run in antagonist mode (to identify antagonist compounds), AR-LBD is added to ligand test compounds, followed by addition of a mixture of DHT agonist, fluorescein-coactivator peptide, and Tb-anti-GST antibody. The concentration of DHT agonist used in this mode is the EC80 concentration as determined by first running the assay in agonist mode. An example of data produced in the antagonist mode is shown in the figure below.

LanthaScreen™ TR-FRET PPAR alpha Competitive Binding Assay Kit, rabbit

This kit contains Rabbit Tb-Anti-GST antibody; other kit components are the same as kit PV4892:

The LanthaScreen® TR-FRET PPAR alpha Competitive Binding Assay provides a sensitive and robust method for high-throughput screening (HTS) of ligands for peroxisome proliferator-activated receptor alpha (PPAR alpha). The kit uses a terbium-labeled anti-GST antibody, a fluorescent small-molecule pan-PPAR ligand (Fluormone™ Pan-PPAR Green), and a human PPAR alpha ligand-binding domain (LBD) that is tagged with glutathione S-transferase (GST), in a homogeneous mix-and-read assay format.

To assay:
When running the LanthaScreen® TR-FRET PPAR alpha Competitive Binding Assay, Fluormone™ Pan-PPAR Green is added to ligand test compounds followed by addition of a mixture of the PPAR alpha-LBD and terbium anti-GST antibody. When the Fluormone™ Pan-PPAR Green is bound to PPAR alpha, energy transfer from the terbium-labeled antibody to the tracer occurs, and a high TR-FRET ratio is observed. Competitive ligand binding to PPAR alpha is detected by a test compound’s ability to displace the tracer, which results in a loss of FRET between the antibody and the tracer. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and can be used to determine the IC50 from a dose response curve of the compound (Figure 1). This type of binding assay is analogous to radioligandbased assays, except that it eliminates handling of radioactivity and enables a homogeneous "addition-only" format.

LanthaScreen™ TR-FRET PPAR delta Competitive Binding Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15144:

The LanthaScreen® TR-FRET PPAR delta Competitive Binding Assay provides a sensitive and robust method for high-throughput screening (HTS) of ligands for peroxisome proliferator-activated receptor delta (PPAR delta). The kit uses a terbium-labeled anti-GST antibody, a fluorescent small-molecule pan-PPAR ligand (Fluormone™ Pan-PPAR Green), and a human PPAR delta ligand-binding domain (LBD) that is tagged with glutathione S-transferase (GST), in a homogeneous mix-and-read assay format.

To assay:
When running the LanthaScreen® TR-FRET PPAR delta Competitive Binding Assay, Fluormone™ Pan-PPAR Green is added to ligand test compounds, followed by addition of a mixture of the PPAR delta-LBD and terbium anti-GST antibody. When the Fluormone™ Pan-PPAR Green is bound to PPAR delta, energy transfer from the terbium-labeled antibody to the tracer occurs, and a high TR-FRET ratio is observed. Competitive ligand binding to PPAR delta is detected by a test compound’s ability to displace the tracer, which results in a loss of FRET between the antibody and the tracer. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and can be used to determine the IC50 from a dose response curve of the compound (Figure 1). This type of binding assay is analogous to radioligandbased assays, except that it eliminates handling of radioactivity and enables a homogeneous, "addition-only" format.

LanthaScreen™ TR-FRET RAR gamma Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15123:

The LanthaScreen® TR-FRET Retinoic Acid Receptor (RAR) gamma Coactivator Assay Kit provides a sensitive and robust method for high-throughput screening of potential RAR gamma ligands as agonists of coactivator recruitment. The homogeneous mix-and-read assay format results in a ligand EC50 composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (Figure 1).

How it works

The LanthaScreen® TR-FRET RAR gamma Coactivator Assay Kit includes a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and a human RAR gamma ligand-binding domain (RAR gamma-LBD) that is tagged with glutathione-S-transferase (GST). To assay, RAR gamma-LBD is added to ligand test compounds, followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-anti-GST antibody. After room temperature incubation, the TR-FRET 520:495 emission ratio is calculated and used to determine the EC50 from a dose response curve of the compound.

Contents and Storage:

The LanthaScreen® TR-FRET RAR gamma Coactivator Assay Kit contains RAR gamma-LBD (GST) protein, fluorescein-labeled PGC1a coactivator peptide, Tb-anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or +4°C).

LanthaScreen™ TR-FRET ERR gamma Coactivator Assay Kit, rabbit

This kit contains Rabbit Tb-Anti-GST antibody; other kit components are the same as kit PV4408:

The LanthaScreen® TR-FRET Estrogen Related Receptor (ERR) gamma Coactivator Assay Kit provides a sensitive and robust method for high-throughput screening of potential ERR gamma ligands as antagonists/inverse agonists of coactivator displacement. The homogeneous mix-and-read assay format results in a ligand EC50 composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and displace coactivator peptide (Figure 1).

How it works

The LanthaScreen® TR-FRET ERR gamma Coactivator Assay Kit includes a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and a human ERR gamma ligand-binding domain (ERR gamma-LBD) that is tagged with glutathione-S-transferase (GST). To assay, ERR gamma-LBD is added to test compounds, followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-anti- GST antibody. After room temperature incubation, the TR-FRET 520:495 emission ratio is calculated and used to determine the EC50 from a dose response curve of the compound.

Contents and Storage:

The LanthaScreen® TR-FRET ERR gamma Coactivator Assay Kit contains ERR gamma-LBD (GST) protein, fluorescently labeled PGC1a coactivator peptide, Tb-anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or +4°C).

LanthaScreen™ TR-FRET ERR alpha Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15130:

The LanthaScreen® ERR (estrogen related receptor) alpha TR-FRET Coactivator Assay provides a sensitive and robust method for high-throughput screening of potential ERR alpha ligands as inverse agonists (sometimes referred to as antagonists) of coactivator displacement. The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and an ERR alpha ligand-binding domain (ERR alpha-LBD) that is tagged with glutathione-S-transferase (GST), in a homogeneous mix-and-read assay format.


In the LanthaScreen® ERR alpha TR-FRET Coactivator Assay, ERR alpha-LBD is added to ligand test compounds, followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-labeled anti-GST antibody. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and can be used to determine the EC50 from a dose response curve of the compound. Based on the biology of the ERR alpha-coactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and displace coactivator peptide (Figure 1).


Contents and Storage:


The LanthaScreen® TR-FRET ERR alpha Coactivator Assay Kit contains ERR alpha-LBD (GST) protein, fluorescently labeled PGC1a coactivator peptide, Tb-labeled anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or +4°C).

PolarScreen™ Progesterone Receptor Competitor Assay Kit, Red

The PolarScreen™ Progesterone Receptor Competitor Assay Kit, Red, provides a sensitive and efficient method for high-throughput, fluorescence polarization-based screening of potential progesterone receptor (PR) ligands. The kit uses insect cell-expressed, human progesterone receptor ligand binding domain tagged with glutathione-S-transferase (GST) (also available separately) and a novel, high-affinity, fluorescent progesterone ligand (Fluormone™ PL Red) in a homogenous, mix-and-read assay format.

This kit produces a red color read-out; a "green" kit is also available. Both kits suitably determine the IC50s of competitive compounds. Color choice depends on the spectral properties of the compounds to be screened and the available instrumentation. For additional information or assistance contact us at drugdiscoverytech@lifetech.com.

The PolarScreen Progesterone Receptor Competitor Assay is:

• Complete & ready-to-use out of the box—all reagents included, just add your test compounds
• High throughput compatible—fluorescence polarization assays in a 384-well plate
• Convenient—components available in bulk sizes for larger screening needs

How the Assay Works
An N-terminal fusion of glutathione transferase to the ligand-binding domain of the human progesterone receptor (PR-LBD(GST)) is added to a fluorescently-tagged progesterone ligand (Fluormone PL Red) in the presence of competitor test compounds in microwell plates. The presence of effective competitors prevents the formation of a PL Red/PR-LBD(GST) complex resulting in a decrease of the polarization value. The shift in polarization value in the presence of test compounds is used to determine relative affinity of test compounds for PR-LBD(GST).

Contact us for bulk quantities or for assistance with other nuclear receptor assay needs, from assay development to library screening and beyond.

LanthaScreen™ TR-FRET LXR beta Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15129:

The LanthaScreen® TR-FRET LXR (liver X receptor) beta Coactivator Assay provides a sensitive and robust method for high-throughput screening of potential LXR beta ligands as agonists of coactivator recruitment. The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and an LXR beta ligand-binding domain (LBD) that is tagged with glutathione-S-transferase (GST), in a homogeneous mix-and-read assay format.

How it works:
In the LanthaScreen® TR-FRET LXR beta Coactivator Assay, LXR beta-LBD is added to ligand test compounds followed by the addition of a mixture of the fluorescein-coactivator peptide and Tb-labeled anti-GST antibody. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and can be used to determine the EC50 from a dose response curve of the compound. Based on the biology of the LXR beta-coactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (Figure 1).

Contents and Storage:
The LanthaScreen® TR-FRET LXR beta Coactivator Assay Kit contains LXR beta-LBD (GST) protein, fluorescently labeled D22 coactivator peptide, Tb-labeled anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or +4°C).

LanthaScreen™ TR-FRET LXR alpha Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15128:

The LanthaScreen® TR-FRET LXR (liver X receptor) alpha Coactivator Assay provides a sensitive and robust method for high-throughput screening of potential LXR alpha ligands as agonists of coactivator recruitment. The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and an LXR alpha ligand-binding domain (LBD) that is tagged with glutathione-S-transferase (GST), in a homogeneous mix-and-read assay format.

In the LanthaScreen® TR-FRET LXR alpha Coactivator Assay, LXR alpha-LBD is added to ligand test compounds followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-labeled anti-GST antibody. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and can be used to determine the EC50 from a dose response curve of the compound. Based on the biology of the LXR alpha-coactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (Figure 1).

Contents and Storage:
The LanthaScreen® TR-FRET LXR alpha Coactivator Assay Kit contains LXR alpha-LBD (GST) protein, fluorescently labeled TRAP220/DRIP-2 coactivator peptide, Tb-labeled anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or +4°C).

PolarScreen™ Androgen Receptor Competitor Assay Kit, Green

The PolarScreen™ Androgen Receptor Competitor Assay Kit, Green, provides a sensitive and efficient method for high-throughput, fluorescence polarization-based screening of potential androgen receptor (AR) ligands. The kit uses insect cell-expressed, rat AR-ligand binding domain tagged with glutathione-S-transferase (GST) and histidine (also available separately), plus a novel, high-affinity, fluorescent androgen ligand (Fluormone™ AL Green) in a homogenous, mix-and-read assay format.

This kit produces a green color read-out; a "red" kit is also available. Both kits suitably determine the IC50s of competitive compounds. Color choice depends on the spectral properties of the compounds to be screened and the available instrumentation. For additional information or assistance contact us at drugdiscoverytech@lifetech.com.

The PolarScreen Androgen Receptor Competitor Assay is:

• Complete & ready-to-use out of the box—all reagents included, just add your test compounds
• High throughput compatible—fluorescence polarization assays in a 384-well plate
• Convenient—components available in bulk sizes for larger screening needs

How the Assay Works
The kit uses the rat AR ligand-binding domain tagged with His and GST [AR-LBD(His-GST)]. AR-LBD(His-GST) is added to a fluorescently-tagged androgen ligand (FluormoneAL Green) in the presence of competitor test compounds in microwell plates. The presence of effective competitors prevents the formation of a AL Green/AR-LBD(His-GST) complex, resulting in a decrease of the polarization value due to ligand displacement caused by a competitor. The shift in polarization value in the presence of test compounds is used to determine relative affinity of test compounds for AR-LBD(His-GST).

Contact us for bulk quantities or for assistance with other nuclear receptor assay needs, from assay development to library screening and beyond.

LanthaScreen™ TR-FRET PXR (SXR) Competitive Binding Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15142:

The LanthaScreen® TR-FRET PXR (SXR) Competitive Binding Assay Kit provides a sensitive and robust method for high-throughput screening (HTS) of ligands for the pregnane X receptor (PXR), also known as the steroid and xenobiotic receptor (SXR). The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescent small-molecule PXR ligand (Fluormone™ PXR (SXR) Green), and a human PXR (SXR) ligand-binding domain that is tagged with glutathione S-transferase (GST) in a homogeneous mix-and-read assay format.

To assay:
When running the LanthaScreen® TR-FRET PXR (SXR) competitive binding assay, a Tb-labeled anti-GST antibody is used to indirectly label the receptor by binding to its GST tag. Competitive ligand binding is detected by a test compound’s ability to displace a fluorescent ligand (tracer) from the receptor, which results in a loss of FRET signal between the Tb-anti-GST antibody and the tracer (Figure 1). This type of binding assay is analogous to radioligand-based assays, except that it eliminates handling of radioactivity and enables a homogeneous, “addition-only " format.

LanthaScreen™ TR-FRET PPAR gamma Competitive Binding Assay Kit, rabbit

This kit contains Rabbit Tb-Anti-GST antibody; other kit components are the same as kit PV4894:

The LanthaScreen® TR-FRET PPAR gamma Competitive Binding Assay provides a sensitive and robust method for high-throughput screening (HTS) of ligands for peroxisome proliferator-activated receptor-gamma (PPAR gamma). The kit uses a terbium-labeled anti-GST antibody, a fluorescent small-molecule pan-PPAR ligand (Fluormone™ Pan-PPAR Green), and human PPAR gamma ligand-binding domain (LBD) that is tagged with glutathione S-transferase (GST) in a homogeneous mix-and-read assay format.

To assay:
When running the LanthaScreen® TR-FRET PPAR gamma Competitive Binding Assay, Fluormone™ Pan-PPAR Green is added to ligand test compounds followed by addition of a mixture of the PPAR gamma-LBD and terbium anti-GST antibody. When the Fluormone™ Pan-PPAR Green is bound to PPAR gamma, energy transfer from the terbium-labeled antibody to the tracer occurs, and a high TR-FRET ratio is observed. Competitive ligand binding to PPAR gamma is detected by a test compound’s ability to displace the tracer, which results in a loss of FRET between the antibody and the tracer. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and can be used to determine the IC50 from a dose response curve of the compound (Figure 1). This type of binding assay is analogous to radioligand-based assays, except that it eliminates handling of radioactivity and enables a homogeneous, "addition-only" format.

LanthaScreen™ TR-FRET PPAR gamma Competitive Binding Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15145:

The LanthaScreen® TR-FRET PPAR gamma Competitive Binding Assay provides a sensitive and robust method for high-throughput screening (HTS) of ligands for peroxisome proliferator-activated receptor-gamma (PPAR gamma). The kit uses a terbium-labeled anti-GST antibody, a fluorescent small-molecule pan-PPAR ligand (Fluormone™ Pan-PPAR Green), and human PPAR gamma ligand-binding domain (LBD) that is tagged with glutathione S-transferase (GST) in a homogeneous mix-and-read assay format.

To assay:
When running the LanthaScreen® TR-FRET PPAR gamma Competitive Binding Assay, Fluormone™ Pan-PPAR Green is added to ligand test compounds followed by addition of a mixture of the PPAR gamma-LBD and terbium anti-GST antibody. When the Fluormone™ Pan-PPAR Green is bound to PPAR gamma, energy transfer from the terbium-labeled antibody to the tracer occurs, and a high TR-FRET ratio is observed. Competitive ligand binding to PPAR gamma is detected by a test compound’s ability to displace the tracer, which results in a loss of FRET between the antibody and the tracer. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and can be used to determine the IC50 from a dose response curve of the compound (Figure 1). This type of binding assay is analogous to radioligand-based assays, except that it eliminates handling of radioactivity and enables a homogeneous, "addition-only" format.

LanthaScreen™ TR-FRET RXR beta Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15120:

The LanthaScreen® TR-FRET Retinoid X Receptor (RXR) beta Coactivator Assay Kit provides a sensitive and robust method for high-throughput screening of potential RXR beta ligands as agonists of coactivator recruitment. The homogeneous mix-and-read assay format results in a ligand EC50 composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (Figure 1).

How it works

The LanthaScreen® TR-FRET RXR beta Coactivator Assay Kit includes a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and a human RXR beta ligand-binding domain (RXR beta-LBD) that is tagged with glutathione-S-transferase (GST). To assay, the RXR beta-LBD is added to ligand test compounds, followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-anti-GST antibody. After room temperature incubation, the TR-FRET 520:495 emission ratio is calculated and used to determine the EC50 from a dose response curve of the compound

Contents and Storage:

The LanthaScreen® TR-FRET RXR beta Coactivator Assay Kit contains RXR beta-LBD (GST) protein, fluorescein-labeled D22 coactivator peptide, Tb-anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or +4°C).

PolarScreen™ ER Alpha Competitor Assay, Green

The PolarScreen™ ER (Estrogen Receptor) Alpha Competitor Assay Kit, Green, provides a sensitive and efficient method for high-throughput, fluorescence polarization-based screening of potential ER alpha ligands. The kit uses insect cell-expressed, full-length, native (untagged) human estrogen receptor alpha (available separately, Cat. No. A15674) and a novel, high-affinity, fluorescent estrogen ligand (Fluormone ES2 Green) in a homogenous, mix-and-read assay format.

This kit produces a green color read-out; a "red" kit is also available. Both kits suitably determine the IC50s of competitive compounds. Color choice depends on the spectral properties of the compounds to be screened and the available instrumentation. For additional information or assistance contact drugdiscoverytech@lifetech.com.

PolarScreen™ ER Alpha Competitor Assay, Green, is:

• Complete & ready-to-use out of the box—all reagents included, just add your test compounds
• High throughput compatible—800 x 20 µL fluorescence polarization assays in a 384-well plate
• Convenient—available in bulk sizes for larger screening needs

How the Assay Works
Full length ER alpha is added to a fluorescent estrogen ligand to form an ER-Fluormone ES2 complex. This complex is added to individual test compounds in multiwell plates. To determine relative affinity, the assay measures fluorescence polarization. Competing test compounds will displace the Fluormone ES2 ligand from ER alpha, permitting it to tumble rapidly and resulting in low polarization values. A shift in the fluorescence polarization value in the presence of test compound is used to determine the relative affinity of test compounds for ER alpha.

All components are manufactured under the strictest quality parameters. This product's performance, per the Certificate of Analysis, is guaranteed for 6 months after purchase. Contact us for bulk quantities or for assistance with other nuclear receptor assay needs, from assay development to library screening and beyond.

LanthaScreen™ TR-FRET ER beta Competitive Binding Kit

The LanthaScreen® TR-FRET ER beta Competitive Binding Kit provides a sensitive and robust method for high-throughput screening (HTS) of ligands for estrogen receptor (ER) beta. The kit uses a human ER beta ligand-binding domain (LBD) that is tagged with glutathione S-transferase (GST), a terbium-labeled anti-GST antibody, and a fluorescent small-molecule ER ligand (Fluormone™ ES2) in a homogeneous mix-and-read assay format.

The Lanthascreen ER beta Competitive Binding Assay is:

• Complete & ready-to-use out of the box—all reagents included, just add your test compounds
• High throughput compatible—TR-FRET assays in a 384-well plate
• Convenient—components available in bulk sizes for larger screening needs

LanthaScreen™ TR-FRET PPAR gamma Coactivator Assay Kit, rabbit

This kit contains Rabbit Tb-Anti-GST antibody; other kit components are the same as kit PV4548:

The LanthaScreen® TR-FRET PPAR gamma Coactivator Assay Kit provides a sensitive and robust method for high-throughput screening of potential PPAR gamma ligands as agonists or antagonists of ligand-dependent coactivator recruitment. The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and a Peroxisome Proliferator Activated Receptor (PPAR) gamma ligand-binding domain (PPAR gamma-LBD) that is tagged with glutathione-S-transferase (GST), in a homogenous mix-and-read assay format.

Agonist mode
To run the LanthaScreen® TR-FRET Peroxisome Proliferator Activated gamma Receptor Coactivator Assay in agonist mode (to identify agonist compounds), PPAR gamma-LBD is added to ligand test compounds followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-anti-GST antibody. After an incubation period at room temperature, the TR-FRET 520:495 emission ratio is calculated and used to determine the EC50 from a dose response curve of the compound. Based on the biology of the PPAR gamma-coactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (Figure 1).

Antagonist mode
When the LanthaScreen® TR-FRET Peroxisome Proliferator Activated gamma Receptor Coactivator Assay is run in antagonist mode (to identify antagonist compounds), PPAR gamma-LBD is added to ligand test compounds followed by addition of a mixture of agonist, fluores-cein-coactivator peptide, and Tb-anti-GST antibody. The concentration of agonist used in this mode is the EC80 concentration as determined by first running the assay in agonist mode (Figure 2).

Contents and Storage:
The LanthaScreen® TR-FRET PPARγ Coactivator Assay Kit contains PPAR gamma-LBD (GST) protein, fluorescently labeled TRAP220/ DRIP-2 coactivator peptide, Tb-anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or +4°C).

LanthaScreen™ TR-FRET VDR Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15127:

The LanthaScreen® TR-FRET Vitamin D Receptor (VDR) Coactivator Assay Kit provides a sensitive and robust method for high-throughput screening of potential VDR ligands as agonists of coactivator recruitment. The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and a VDR ligand-binding domain (VDR-LBD) that is tagged with glutathione-S-transferase (GST), in a homogenous mix-and-read assay format.

The assay
To run the LanthaScreen® TR-FRET VDR Coactivator Assay, VDR-LBD is added to ligand test compounds, followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-anti-GST antibody. After room temperature incubation, the TR-FRET 520:495 emission ratio is calculated and used to determine the EC50 from a dose response curve of the compound. Based upon the biology of the VDRcoactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (Figure 1).

Contents and Storage:
The LanthaScreen® TR-FRET VDR Coactivator Assay Kit contains the VDR-LBD (GST) protein, fluorescein-labeled TRAP220/DRIP-2 coactivator peptide, Tb-anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or +4°C).

LanthaScreen™ TR-FRET ER alpha Coactivator Assay Kit

The LanthaScreen® TR-FRET ER alpha Coactivator Assay Kit provides a sensitive and robust method for high-throughput screening of potential estrogen receptor (ER) alpha ligands as agonists or antagonists of ligand-dependent coactivator recruitment. The kit uses an ER alpha ligand-binding domain (ER alpha-LBD) tagged with glutathione-S-transferase (GST), a terbium (Tb)-labeled anti-GST antibody, and a fluorescein-labeled coactivator peptide in a homogenous mix-and-read assay format.

Agonist Mode
To run the LanthaScreen TR-FRET ER alpha Coactivator Assay in agonist mode (to identify agonist compounds), ER alpha-LBD is added to ligand test compounds, followed by the addition of a mixture of fluorescein-coactivator peptide and Tb-anti-GST antibody. After incubation at room temperature, the TR-FRET 520:495 nm emission ratio is calculated and used to determine the EC50 from a dose response curve of the compound. Based on the biology of the ER alpha-coactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide.

Antagonist Mode
To run the LanthaScreen TR-FRET ER alpha Coactivator Assay in antagonist mode (to identify antagonist compounds), ER alpha-LBD is added to ligand test compounds, followed by addition of a mixture of agonist, fluorescein-coactivator peptide, and terbium (Tb)-labeled anti-GST antibody. The concentration of agonist used in this mode is the EC80 concentration as determined by first running the assay in agonist mode.

LanthaScreen™ TR-FRET RAR beta Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15137:

The LanthaScreen® TR-FRET RAR (retinoic acid receptor) beta Coactivator Assay Kit provides a sensitive and robust method for highthroughput screening of potential RAR beta ligands as agonists of ligand-dependent coactivator recruitment. The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and a human recombinant RAR beta ligand-binding domain (RAR beta-LBD) that is tagged with glutathione-S-transferase (GST) in a homogeneous, mix-and-read assay format.

When running the LanthaScreen® TR-FRET RAR beta coactivator assay in agonist mode to identify agonist compounds, RAR beta-LBD is added to ligand test compounds, followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-labeled anti-GST antibody. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and can be used to determine the EC50 from a dose response curve of the compound. Based on the biology of the RAR beta-coactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (Figure 1).

Contents and Storage:
The LanthaScreen® TR-FRET RAR beta Coactivator Assay Kit contains RAR beta-LBD (GST) protein, fluorescently labeled SRC2-2 coactivator peptide, Tb-labeled anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or +4°C).

LanthaScreen™ TR-FRET FXR Coactivator Assay Kit, rabbit

This kit contains Rabbit Tb-Anti-GST antibody; other kit components are the same as kit PV4833:

The LanthaScreen® TR-FRET FXR (farnesoid X receptor) Coactivator Assay Kit provides a sensitive and robust method for high-throughput screening of potential FXR ligands as agonists of coactivator recruitment. The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein- labeled coactivator peptide, and an FXR ligand-binding domain (FXR-LBD) that is tagged with glutathione-S-transferase (GST), in a homogeneous, mix-and-read assay format.

To assay:
When running the LanthaScreen® TR-FRET FXR coactivator assay in agonist mode, FXR-LBD is added to ligand test compounds followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-labeled anti-GST antibody. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and used to determine the EC50 from a dose response curve of the compound. Based on the biology of the FXR-coactivator peptide interaction, the ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (Figure 1).

LanthaScreen™ TR-FRET Glucocorticoid Receptor Competitive Binding Kit

The LanthaScreen® TR-FRET Glucocorticoid Receptor Competitive Binding Assay Kit provides a sensitive and robust method for high-throughput screening (HTS) of ligands for glucocorticoid receptor (GR). The kit uses a human GR ligand-binding domain (GR-LBD) tagged with glutathione S-transferase (GST) (also available separately), a terbium-labeled anti-GST antibody, and a fluorescent small-molecule GR ligand (Fluormone™ GS1) in a homogeneous mix-and-read assay format.

The Lanthascreen Gluococorticoid Receptor Competitive Binding Assay is:

• Complete & ready-to-use out of the box—all reagents included, just add your test compounds
• High throughput compatible—TR-FRET assays in a 384-well plate
• Convenient—components available in bulk sizes for larger screening needs

PolarScreen™ Vitamin D Receptor Competitor Assay Kit, Red

The PolarScreen™ Vitamin D Receptor Competitor Assay Kit, Red, provides a sensitive and efficient method for high-throughput, fluorescence polarization-based screening of potential vitamin D receptor (VDR) ligands. The kit uses insect cell-expressed, human full-length VDR (also available separately) and a novel, high-affinity, fluorescent VDR ligand (Fluormone™ VDR Red) in a homogenous, mix-and-read assay format.

This kit produces a red color read-out and is suitable to determine the IC50s of competitive compounds. For additional information or assistance contact us at drugdiscoverytech@lifetech.com.

The PolarScreen Vitamine D Receptor Competitor Assay is:

• Complete & ready-to-use out of the box—all reagents included, just add your test compounds
• High throughput compatible—fluorescence polarization assays in a 384-well plate
• Convenient—components available in bulk sizes for larger screening needs

How the Assay Works
VDR is added to a fluorescent VDR ligand (Fluormone VDR Red) to form a receptor/tracer complex, resulting in a high polarization value. This complex is then added to individual test compounds in microwell plates. Competitors displace the tracer from the complex, causing the fluorescent ligand to tumble more rapidly during its fluorescence lifetime, resulting in a low polarization value. Noncompetitors will not displace the fluorescent ligand from the complex; therefore, the polarization value will remain high. The shift in polarization value in the presence of test compounds is used to determine relative affinity of test compounds for VDR (see figure).

Contact us for bulk quantities or for assistance with other nuclear receptor assay needs, from assay development to library screening and beyond.

PolarScreen™ PPARγ-Competitor Assay Kit, Green

The PPARγ (Peroxisome Proliferator-Activated Receptor-gamma) Competitor Assay, Green uses the human-derived recombinant PPARγ ligand-binding domain (PPARγ-LBD) tagged with an N-terminal GST-tag and a novel, tight-binding, selective fluorescent PPARγ ligand (Fluormone™ PPARγ Green) in a homogenous, mix-and-read assay format. PPARγ-LBD/Fluormone™ PPARγ Green complex produces high polarization. This complex is then added to individual test compounds in microwell plates. Competitors displace the fluorescent Fluormone™ PPARγ Green Ligand from the PPARγ-LBD/Fluormone™ PPARγ Green complex, causing the fluorescent ligand to tumble rapidly during its fluorescence lifetime, resulting in a low polarization value. Noncompetitors will not displace the fluorescent ligand from the complex, so the polarization value remains high. The shift in polarization value in the presence of the test compounds is used to determine relative affinity of test compounds for the PPARγ-LBD.

LanthaScreen™ TR-FRET FXR Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15140:

The LanthaScreen® TR-FRET FXR (farnesoid X receptor) Coactivator Assay Kit provides a sensitive and robust method for high-throughput screening of potential FXR ligands as agonists of coactivator recruitment. The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein- labeled coactivator peptide, and an FXR ligand-binding domain (FXR-LBD) that is tagged with glutathione-S-transferase (GST), in a homogeneous, mix-and-read assay format.

To assay:
When running the LanthaScreen® TR-FRET FXR coactivator assay in agonist mode, FXR-LBD is added to ligand test compounds followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-labeled anti-GST antibody. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and used to determine the EC50 from a dose response curve of the compound. Based on the biology of the FXR-coactivator peptide interaction, the ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (Figure 1).

PolarScreen™ Androgen Receptor Competitor Assay Kit, Red

The PolarScreen™ Androgen Receptor Competitor Assay Kit, Red, provides a sensitive and efficient method for high-throughput, fluorescence polarization-based screening of potential androgen receptor (AR) ligands. The kit uses insect cell-expressed rat AR ligand binding domain tagged with glutathione-S-transferase (GST) and histidine (also available separately), plus a novel, high-affinity, fluorescent androgen receptor ligand (Fluormone AL Red) in a homogenous, mix-and-read assay format.

This kit produces a red color read-out; a "green" kit is also available. Both kits suitably determine the IC50s of competitive compounds. Color choice depends on the spectral properties of the compounds to be screened and the available instrumentation. For additional information or assistance contact us at drugdiscoverytech@lifetech.com.

The PolarScreen Androgen Receptor Competitor Assay is:

• Complete & ready-to-use out of the box—all reagents included, just add your test compounds
• High throughput compatible—fluorescence polarization assays in a 384-well plate
• Convenient—components available in bulk sizes for larger screening needs

How the Assay Works
The kit uses the rat AR ligand-binding domain tagged with His and GST [AR-LBD(His-GST)]. AR-LBD(His-GST) is added to a fluorescently-tagged androgen ligand (FluormoneAL Red) in the presence of competitor test compounds in microwell plates. Competitors displace the fluorescent FluormoneAL Red Ligand from the AR-LBD/FluormoneAL Red complex, causing the fluorescent ligand to tumble rapidly during its fluorescence lifetime, resulting in a low polarization value. Noncompetitors will not displace the fluorescent ligand from the complex; therefore, the polarization value remains high. The shift in polarization value in the presence of the test compounds is used to determine relative affinity of test compounds for the AR-LBD.

Contact us for bulk quantities or for assistance with other nuclear receptor assay needs, from assay development to library screening and beyond.

LanthaScreen™ TR-FRET ER beta Coactivator Assay Kit

The LanthaScreen® TR-FRET ER beta Coactivator Assay Kit provides a sensitive and robust method for high-throughput screening of potential estrogen receptor (ER) beta ligands as agonists or antagonists of ligand-dependent coactivator recruitment. The kit uses a ER beta ligand-binding domain (ER beta-LBD) that is tagged with glutathione-S-transferase (GST), a terbium (Tb)-labeled anti-GST antibody, and a fluorescein-labeled coactivator peptide in a homogenous mix-and-read assay format.

Agonist Mode
To run the LanthaScreen TR-FRET ER beta Coactivator Assay in agonist mode (to identify agonist compounds), ER beta-LBD is added to ligand test compounds followed by the addition of a mixture of fluorescein-coactivator peptide and Tb-anti-GST antibody. After room temperature incubation, the TR-FRET 520:495 emission ratio is calculated and used to determine the EC50 from a dose response curve of the compound. Based upon the biology of the ER beta-coactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide.

Antagonist Mode
When the LanthaScreen TR-FRET ER beta Coactivator Assay Kit is run in antagonist mode (to identify antagonist compounds), ER beta-LBD is added to ligand test compounds followed by the addition of a mixture of agonist, fluorescein-coactivator peptide, and Tb-anti-GST antibody. The concentration of agonist used in this mode is the EC80 concentration as determined by first running the assay in agonist mode.

PolarScreen™ ER Alpha Competitor Assay, Red

The PolarScreen™ ER (Estrogen Receptor) Alpha Competitor Assay Kit, Red, provides a sensitive and efficient method for high-throughput, fluorescence polarization-based screening of potential ER alpha ligands. The kit uses insect cell-expressed, full-length, native (untagged) human estrogen receptor alpha (available separately, Cat. No. A15674) and a novel, high-affinity, fluorescent estrogen ligand (Fluormone EL Red) in a homogenous, mix-and-read assay format.

This kit produces a red color read-out; a "green" kit is also available. Both kits suitably determine the IC50s of competitive compounds. Color choice depends on the spectral properties of the compounds to be screened and the available instrumentation. For additional information or assistance contact drugdiscoverytech@lifetech.com.

PolarScreen™ ER Alpha Competitor Assay, Red, is:

• Complete & ready-to-use out of the box—all reagents included, just add your test compounds
• High throughput compatible—800 x 20 µL fluorescence polarization assays in a 384-well plate
• Convenient—available in bulk sizes for larger screening needs

How the Assay Works
Full length ER alpha is added to a fluorescent estrogen ligand to form an ER-Fluormone EL complex. This complex is added to individual test compounds in multiwell plates. To determine relative affinity, the assay measures fluorescence polarization. Competing test compounds will displace the Fluormone EL ligand from ER alpha, permitting it to tumble rapidly and resulting in low polarization values. A shift in the fluorescence polarization value in the presence of test compound is used to determine the relative affinity of test compounds for ER alpha.

All components are manufactured under the strictest quality parameters. This product's performance, per the Certificate of Analysis, is guaranteed for 6 months after purchase. Contact us for bulk quantities or for assistance with other nuclear receptor assay needs, from assay development to library screening and beyond.

LanthaScreen™ TR-FRET TR alpha Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15136:

The LanthaScreen® TR-FRET TR (thyroid receptor) alpha Coactivator Assay Kit provides a sensitive and robust method for highthroughput screening of potential TR alpha ligands as agonists of ligand-dependent coactivator recruitment. The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and a human recombinant TR alpha ligand-binding domain (TR alpha-LBD) that is tagged with glutathione-S-transferase (GST) in a homogeneous, mix-and-read assay format.

To Assay:
When performing the LanthaScreen® TR-FRET TR alpha coactivator assay, TR alpha-LBD is added to ligand test compounds followed by addition of a mixture of the fluorescein-coactivator peptide and Tb anti-GST antibody. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and used to determine the EC50 from a dose response curve of the compound. Based on the biology of the TR alpha-coactivator peptide interaction, the ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, induce a conformational change, and recruit coactivator peptide (Figure 1).

Contents and Storage:
The LanthaScreen® TR-FRET TR alpha Coactivator Assay Kit contains TR alpha-LBD (GST) protein, fluorescently labeled SRC2-2 coactivator peptide, Tb-labeled anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or +4°C).

LanthaScreen™ TR-FRET PPAR alpha Coactivator Assay Kit, rabbit

This kit contains Rabbit Tb-Anti-GST antibody; other kit components are the same as kit PV4684:

The LanthaScreen® TR-FRET PPAR (peroxisome proliferator activated receptor) alpha Coactivator Assay provides a sensitive and robust method for high-throughput screening of potential PPAR alpha ligands as agonists or antagonists of ligand-dependent coactivator recruitment. The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and a human recombinant PPAR alpha ligand-binding domain (PPAR alpha-LBD) that is tagged with glutathione-S-transferase (GST) in a homogeneous mix-and-read assay format.

Agonist mode:
When running the LanthaScreen® TR-FRET PPAR alpha Coactivator Assay in agonist mode (to identify agonist compounds), PPAR alpha- LBD is added to ligand test compounds followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-labeled anti-GST antibody. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and can be used to determine the EC50 from a dose response curve of the compound. Based on the biology of the PPAR alpha-coactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (see Figure 1).

Antagonist mode:
When the LanthaScreen® TR-FRET PPAR alpha Coactivator Assay is run in antagonist mode (to identify antagonist compounds), PPAR alpha-LBD is added to ligand test compounds followed by addition of a mixture of agonist, fluorescein-coactivator peptide, and Tb-labeled anti-GST antibody (Figure 2). The concentration of agonist used in this mode is the EC80 concentration as determined by first running the assay in agonist mode.

Contents and Storage:
The LanthaScreen® TR-FRET PPAR alpha Coactivator Assay Kit contains PPAR alpha-LBD (GST) protein, fluorescently labeled PGC1a coactivator peptide, Tb-labeled anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or 4°C).

LanthaScreen™ TR-FRET Glucocorticoid Receptor Coactivator Assay Kit

The LanthaScreen® TR-FRET Glucocorticoid Receptor Coactivator Assay Kit provides a sensitive and robust method for high-throughput screening of potential glucocorticoid receptor (GR) ligands as agonists or antagonists of ligand-dependent coactivator recruitment. The kit uses a human recombinant GR ligand-binding domain (GR-LBD) tagged with glutathione-S-transferase (GST) (also available separately), a terbium (Tb)-labeled anti-GST antibody, and a fluorescein-labeled coactivator peptide in a homogeneous mix-and-read assay format.

Agonist Mode
When running the LanthaScreen TR-FRET Glucocorticoid Receptor Coactivator Assay in agonist mode (to identify agonist compounds), GR-LBD is added to ligand test compounds, followed by the addition of a mixture of fluorescein-coactivator peptide and Tb-labeled anti-GST antibody. After incubation at room temperature, the 520/495 nm TR-FRET ratio is calculated and can be used to determine the EC50 from a dose response curve of the compound. Based on the biology of the GR-coactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (see figure).

Antagonist Mode
When the LanthaScreen TR-FRET Glucocorticoid Receptor Coactivator Assay is run in antagonist mode (to identify antagonist compounds), GR-LBD is added to ligand test compounds followed by the addition of a mixture of agonist, fluorescein-coactivator peptide, and Tb-labeled anti-GST antibody (see figure). The concentration of agonist used in this mode is the EC80 concentration as determined by first running the assay in agonist mode.

LanthaScreen™ TR-FRET CAR Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15141:

The LanthaScreen® TR-FRET Constitutive Androstane Receptor (CAR) Coactivator Assay provides a sensitive and robust method for highthroughput screening (HTS) of potential CAR ligands as agonists of ligand-dependent coactivator recruitment or inverse agonists of liganddependent coactivator displacement. The kit uses a terbium-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and a CAR ligand-binding domain (CAR-LBD) that is tagged with glutathione-S-transferase (GST) in a homogeneous mix-and-read assay format.

To assay:
When running the LanthaScreen® TR-FRET CAR Coactivator Assay, CAR-LBD is added to ligand test compounds followed by addition of a mixture of the fluorescein-coactivator peptide and terbium anti-GST antibody. After an incubation period at room temperature, the 520 nm/ 495 nm TR-FRET ratio is calculated and can be used to determine the EC50 from a dose response curve of the compound. Based on the biology of the CAR-coactivator peptide interaction, this ligand’s EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and either recruit or displace coactivator peptide (Figures 1 and 2).

PolarScreen™ ER Beta Competitor Assay Kit, Red

The PolarScreen™ ER Beta Competitor Assay Kit, Red, provides a sensitive and efficient method for high-throughput, fluorescence polarization-based screening of potential estrogen receptor (ER) beta ligands. The kit uses insect cell-expressed, full-length, native (untagged) human ER beta (A15664) and a novel, high-affinity, fluorescent estrogen ligand (Fluormone™ ES2) in a homogenous, mix-and-read assay format.

This kit produces a red color read-out; a "green" kit is also available (A15890). Both kits suitably determine the IC50s of competitive compounds. Color choice depends on the spectral properties of the compounds to be screened and the available instrumentation. For additional information or assistance email drugdiscoverytech@lifetech.com.

The PolarScreen™ ER Beta Competitor Assay Kit is:

• Complete & ready-to-use out of the box—all reagents included, just add your test compounds
• High throughput compatible—20 µL fluorescence polarization assays in a 384-well plate
• Convenient—available in bulk sizes for larger screening needs

How the Assay Works
Full-length ER beta is added to a fluorescent estrogen ligand to form an ER-Fluormone™ ES2 complex. This complex is added to individual test compounds in multiwell plates. To determine relative affinity, the assay measures fluorescence polarization. Competing test compounds will displace the Fluormone™ ES2 ligand from ER beta, permitting it to tumble rapidly and resulting in low polarization values. A shift in the fluorescence polarization value in the presence of test compound is used to determine the relative affinity of test compounds for ER beta.

All components are manufactured under the strictest quality parameters. This product's performance, per the Certificate of Analysis, is guaranteed for 6 months after purchase. Contact us for bulk quantities or for assistance with other nuclear receptor assay needs, from assay development to library screening and beyond.

LanthaScreen™ TR-FRET TR beta Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15135:

The LanthaScreen® TR-FRET TR (thyroid receptor) beta Coactivator Assay Kit provides a sensitive and robust method for high-throughput screening of potential TR beta ligands as agonists of ligand-dependent coactivator recruitment. The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and a human recombinant TR beta ligand-binding domain (TR beta-LBD) that is tagged with glutathione-S-transferase (GST) in a homogeneous, mix-and-read assay format.

To Assay:
When performing the LanthaScreen® TR-FRET TR beta coactivator assay, TR beta-LBD is added to ligand test compounds followed by addition of a mixture of the fluorescein-coactivator peptide and Tb anti-GST antibody. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and can be used to determine the EC50 from a dose response curve of the compound. Based on the biology of the TR beta-coactivator peptide interaction, the ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, induce a conformational change, and recruit coactivator peptide (Figure 1).

Contents and Storage:
The LanthaScreen® TR-FRET TR beta Coactivator Assay Kit contains TR beta-LBD (GST) protein, fluorescently labeled SRC2-2 coactivator peptide, Tb-labeled anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or +4°C).

LanthaScreen™ TR-FRET LXR beta Coactivator Assay Kit, rabbit

This kit contains Rabbit Tb-Anti-GST antibody; other kit components are the same as kit PV4658:

The LanthaScreen® TR-FRET LXR (liver X receptor) beta Coactivator Assay provides a sensitive and robust method for high-throughput screening of potential LXR beta ligands as agonists of coactivator recruitment. The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and an LXR beta ligand-binding domain (LBD) that is tagged with glutathione-S-transferase (GST), in a homogeneous mix-and-read assay format.

How it works:
In the LanthaScreen® TR-FRET LXR beta Coactivator Assay, LXR beta-LBD is added to ligand test compounds followed by the addition of a mixture of the fluorescein-coactivator peptide and Tb-labeled anti-GST antibody. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and can be used to determine the EC50 from a dose response curve of the compound. Based on the biology of the LXR beta-coactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (Figure 1).

Contents and Storage:
The LanthaScreen® TR-FRET LXR beta Coactivator Assay Kit contains LXR beta-LBD (GST) protein, fluorescently labeled D22 coactivator peptide, Tb-labeled anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or +4°C).

PolarScreen™ Glucocorticoid Receptor Competitor Assay Kit, Red

The PolarScreen™ Glucocorticoid Receptor Competitor Assay Kit, Red, provides a sensitive and efficient method for high-throughput, fluorescence polarization-based screening of potential glucocorticoid receptor (GR) ligands. The kit uses insect cell-expressed, human GR (also available separately) and a novel, high-affinity, fluorescent glucocorticoid ligand (Fluormone™ GS Red) in a homogenous, mix-and-read assay format.

This kit produces a red color read-out; a "green" kit is also available. Both kits suitably determine the IC50s of competitive compounds. Color choice depends on the spectral properties of the compounds to be screened and the available instrumentation. For additional information or assistance, contact drugdiscoverytech@lifetech.com.

The PolarScreen Glucocorticoid Receptor Competitor Assay is:

• Complete & ready-to-use out of the box—all reagents included, just add your test compounds
• High throughput compatible—fluorescence polarization assays in a 384-well plate
• Convenient—components available in bulk sizes for larger screening needs

How the Assay Works
GR is added to a fluorescent glucocorticoid ligand (Fluormone GS Red) in the presence of competitor test compounds in microwell plates. The presence of effective competitors prevents the formation of a GS Red/GR complex, resulting in a decrease of the polarization value. The shift in polarization value in the presence of test compounds is used to determine relative affinity of test compounds for GR. The assay is designed to be carried out at room temperature through use of a coactivator-related stabilizing peptide. Alternatively, the assay may be run at 4°C in the absence of the stabilizing peptide, with insignificant change in GR binding characteristics.

Contact us for bulk quantities or for assistance with other nuclear receptor assay needs, from assay development to library screening and beyond.

PolarScreen™ ER Beta Competitor Assay Kit, Green

The PolarScreen™ ER Beta Competitor Assay Kit, Green, provides a sensitive and efficient method for high-throughput, fluorescence polarization-based screening of potential estrogen receptor (ER) beta ligands. The kit uses insect cell-expressed, full-length, native (untagged) human ER beta (A15664) and a novel, high-affinity, fluorescent estrogen ligand (Fluormone™ ES2) in a homogenous, mix-and-read assay format.

This kit produces a green color read-out; a "red" kit is also available (A15891). Both kits suitably determine the IC50s of competitive compounds. Color choice depends on the spectral properties of the compounds to be screened and the available instrumentation. For additional information or assistance email drugdiscoverytech@lifetech.com.

The PolarScreen™ ER Beta Competitor Assay Kit is:

• Complete & ready-to-use out of the box—all reagents included, just add your test compounds
• High throughput compatible—20 µL fluorescence polarization assays in a 384-well plate
• Convenient—available in bulk sizes for larger screening needs

How the Assay Works
Full-length ER beta is added to a fluorescent estrogen ligand to form an ER-Fluormone™ ES2 complex. This complex is added to individual test compounds in multiwell plates. To determine relative affinity, the assay measures fluorescence polarization. Competing test compounds will displace the Fluormone™ ES2 ligand from ER beta, permitting it to tumble rapidly and resulting in low polarization values. A shift in the fluorescence polarization value in the presence of test compound is used to determine the relative affinity of test compounds for ER beta.

All components are manufactured under the strictest quality parameters. This product's performance, per the Certificate of Analysis, is guaranteed for 6 months after purchase. Contact us for bulk quantities or for assistance with other nuclear receptor assay needs, from assay development to library screening and beyond.

LanthaScreen™ TR-FRET PPAR delta Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15134:

The LanthaScreen® TR-FRET PPAR (peroxisome proliferator activated receptor) delta Coactivator Assay Kit provides a sensitive and robust method for high-throughput screening of potential PPAR delta ligands as agonists of ligand-dependent coactivator recruitment. The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and a human recombinant PPAR delta ligand-binding domain (PPAR delta-LBD) that is tagged with glutathione-S-transferase (GST), in a homogeneous mix-and-read assay format.

When running the LanthaScreen® TR-FRET PPAR delta Coactivator Assay in agonist mode (to identify agonist compounds), PPAR delta-LBD is added to ligand test compounds followed by addition of a mixture of the fluorescein-labeled coactivator peptide and Tb-labeled anti-GST antibody. After an incubation period at room temperature, the TR-FRET ratio of 520/495 is calculated and can be used to determine the EC50 from a dose response curve of the compound. Based on the biology of the PPAR delta-coactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (see Figure 1).

Contents and Storage:
The LanthaScreen® TR-FRET PPAR delta Coactivator Assay Kit contains PPAR delta-LBD (GST) protein, fluorescently labeled C33 coactivator peptide, Tb-anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C or 4°C).

LanthaScreen™ TR-FRET LXR alpha Coactivator Assay Kit, rabbit

This kit contains Rabbit Tb-Anti-GST antibody; other kit components are the same as kit PV4655:

The LanthaScreen® TR-FRET LXR (liver X receptor) alpha Coactivator Assay provides a sensitive and robust method for high-throughput screening of potential LXR alpha ligands as agonists of coactivator recruitment. The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and an LXR alpha ligand-binding domain (LBD) that is tagged with glutathione-S-transferase (GST), in a homogeneous mix-and-read assay format.

In the LanthaScreen® TR-FRET LXR alpha Coactivator Assay, LXR alpha-LBD is added to ligand test compounds followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-labeled anti-GST antibody. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and can be used to determine the EC50 from a dose response curve of the compound. Based on the biology of the LXR alpha-coactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (Figure 1).

Contents and Storage:
The LanthaScreen® TR-FRET LXR alpha Coactivator Assay Kit contains LXR alpha-LBD (GST) protein, fluorescently labeled TRAP220/DRIP-2 coactivator peptide, Tb-labeled anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or +4°C).

LanthaScreen™ TR-FRET ERR beta Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15139:

The LanthaScreen® TR-FRET ERR (estrogen related receptor) beta Coactivator Assay Kit provides a sensitive and robust method for highthroughput screening of potential ERR beta ligands as inverse agonists of ligand-dependent coactivator displacement. The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and a human recombinant ERR beta ligand-binding domain (ERR beta-LBD) that is tagged with glutathione-S-transferase (GST) in a homogeneous mix-and-read assay format.

To assay:

When running the LanthaScreen® ERR beta TR-FRET Coactivator Assay, ERR beta-LBD is added to ligand test compounds followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-labeled anti-GST antibody. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and can be used to determine the EC50 from a dose response curve of the compound.
Based on the biology of the ERR beta-coactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and displace coactivator peptide (see Figure 1).

LanthaScreen™ TR-FRET PPAR alpha Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15133:

The LanthaScreen® TR-FRET PPAR (peroxisome proliferator activated receptor) alpha Coactivator Assay provides a sensitive and robust method for high-throughput screening of potential PPAR alpha ligands as agonists or antagonists of ligand-dependent coactivator recruitment. The kit uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide, and a human recombinant PPAR alpha ligand-binding domain (PPAR alpha-LBD) that is tagged with glutathione-S-transferase (GST) in a homogeneous mix-and-read assay format.

Agonist mode:
When running the LanthaScreen® TR-FRET PPAR alpha Coactivator Assay in agonist mode (to identify agonist compounds), PPAR alpha- LBD is added to ligand test compounds followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-labeled anti-GST antibody. After an incubation period at room temperature, the 520 nm/495 nm TR-FRET ratio is calculated and can be used to determine the EC50 from a dose response curve of the compound. Based on the biology of the PPAR alpha-coactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (see Figure 1).

Antagonist mode:
When the LanthaScreen® TR-FRET PPAR alpha Coactivator Assay is run in antagonist mode (to identify antagonist compounds), PPAR alpha-LBD is added to ligand test compounds followed by addition of a mixture of agonist, fluorescein-coactivator peptide, and Tb-labeled anti-GST antibody (Figure 2). The concentration of agonist used in this mode is the EC80 concentration as determined by first running the assay in agonist mode.

Contents and Storage:
The LanthaScreen® TR-FRET PPAR alpha Coactivator Assay Kit contains PPAR alpha-LBD (GST) protein, fluorescently labeled PGC1a coactivator peptide, Tb-labeled anti-GST antibody, and buffers. Store components as indicated in the assay protocol (-80°C, -20°C, or 4°C).

LanthaScreen™ TR-FRET ER alpha Competitive Binding Kit

The LanthaScreen® TR-FRET ER alpha Competitive Binding Kit provides a sensitive and robust method for high-throughput screening (HTS) of ligands for estrogen receptor (ER) alpha. The kit uses a human ER alpha ligand-binding domain (LBD) that is tagged with glutathione S-transferase (GST), a terbium-labeled anti-GST antibody, and a fluorescent small-molecule ER ligand (Fluormone™ ES2) in a homogeneous mix-and-read assay format.

The Lanthascreen ER alpha Competitive Binding Assay is:

• Complete & ready-to-use out of the box—all reagents included, just add your test compounds
• High throughput compatible—TR-FRET assays in a 384-well plate
• Convenient—components available in bulk sizes for larger screening needs

LanthaScreen™ TR-FRET RXR alpha Coactivator Assay Kit, goat

This kit contains Goat Tb-Anti-GST antibody; other kit components are the same as kit A15138:

The LanthaScreen® TR-FRET Retinoid X Receptor alpha Coactivator Assay provides a sensitive and robust method for high-throughput screening of potential RXR alpha ligands as agonists of ligand-dependent coactivator recruitment. The kit uses a terbium (Tb)-labeled anti- GST antibody, a fluorescein-labeled coactivator peptide, and a human recombinant RXR alpha ligand-binding domain (RXR alpha-LBD) that is tagged with glutathione-S-transferase (GST) in a homogeneous mix-and-read assay format.

To assay:
When running the LanthaScreen® TR-FRET Retinoid X Receptor alpha Coactivator Assay in agonist mode (to identify agonist compounds), RXR alpha-LBD is added to ligand test compounds followed by addition of a mixture of the fluorescein-coactivator peptide and Tb-labeled anti-GST antibody. After an incubation period at room temperature, the TR-FRET ratio of 520/495 is calculated and can be used to determine the EC50 from a dose-response curve of the compound. Based on the biology of the RXR alpha-coactivator peptide interaction, this ligand EC50 is a composite value representing the amount of ligand required to bind to receptor, effect a conformational change, and recruit coactivator peptide (see Figure 1).