Biochemical Nuclear Receptor Assays - Kits

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 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 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).

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).

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).

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 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).

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.

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).

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 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).

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 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 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.

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.