Luc-Screen™ Extended-Glow Luciferase Reporter Gene Assay System, 1000 Assays - FAQs

View additional product information for Luc-Screen™ Extended-Glow Luciferase Reporter Gene Assay System - FAQs (T1034, T1033)

8 product FAQs found

Does serum concentration have an inhibitory effect on the luciferase assay?

For Fetal Bovine Serum (FBS), there is no difference between 10% and 5% FBS. It is worthwhile to note that the type of serum does affect the luciferase assay. We tested the effect of 6 different types of sera (FBS, heat-inactivated FBS, dialyzed FBS, charcoal-treated FBS, donor adult bovine serum, and donor equine serum) on secreted luciferases, e.g. Gaussia, Gaussia-Dura, and Cypridina Luciferases. No noticeable difference was observed among different types of sera except for donor adult bovine serum. Unknown factors in donor adult bovine serum caused up to 35% inhibition in secreted luciferase activity. Therefore, we don’t recommend using donor adult bovine serum for Gaussia, Gaussia-Dura, and Cypridina Luciferases.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

I used a white plate to read the luciferase assay and have very high background readings. Should I use a black plate?

The problems with white plates are related to cross-talk blocking, surface reflectivity and tendency to phosphorescence. We do not recommend using white plates because they give much higher background even if adapted to darkness for 10 minutes. The white plastic does not block the light completely, and some portion of the signal will go through the plastic and will be seen when you measure adjacent wells. The typical situation is if you change from black to white plates, where the background is about doubled and the signal is increased about 10 times. Black plates are recommend for best signal to noise ratio even though the RLU values will be lower. 

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

What is the stability of the secreted luciferase?

Gaussia, Gaussia-Dura, and Cypridina Luciferase are stable in the culture media for greater than 24 hours. Generally, after transfection of CMV driven constructs, we see ever increasing secreted signal between 24 and 72 hours.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

How quickly is luciferase secreted?

The earliest detectable signal will depend on the strength of the promoter. In general, with a strong promoter (such as CMV), significant signal over background can be seen in as little as 20 minutes. However, with a weaker inducible promoter, significant signal over background may take 1-2 hours after induction.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

What instrument filters are required to read the luciferase assays?

We always recommend the luciferases to be read without filters for single luciferase assays. Use of filters reduces the amount of signal captured that may lead to decrease in sensitivity. Filters are required only for dual-spectral assays.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

Which luciferase assays can be used to specifically test media as a sample type?

Gaussia and Cypridina Luciferase assays can be tested on both media and cell lysate sample types. Renilla and Firefly Luciferase assays can only be used on cell lysate as a sample type. 

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

Which luciferase assays do you offer to screen cell lysates and media?

We offer the following luciferase assays (each available in Glow and Flash formats) that provide a highly sensitive assay for transcriptional activity of regulatory elements in mammalian cell culture media and whole cell lysate:

- Thermo Scientific Pierce Gaussia Luciferase assays provide a highly sensitive system for detecting intracellular and secreted luciferase activity from promoter or pathway activation in mammalian cell culture experiments. Gaussia luciferase has greater protein stability and signal brightness than native Firefly or Renilla luciferase. The bioluminescent signal produced by Gaussia luciferase results from the oxidation of coelenterazine. This reaction does not require adenosine triphosphate (ATP) or other cofactors. The light output correlates with the amount of Gaussia protein expressed, which is proportional to the activity of the promoter for Gaussia expression.
Note: Gaussia luciferase is a ~22 kDa protein.

- Thermo Scientific Pierce Renilla Luciferase assays provide a highly sensitive system for detecting intracellular luciferase activity from promoter or pathway activation in mammalian cell culture experiments. The bioluminescent signal produced by green Renilla luciferase results from the oxidation of coelenterazine. This reaction does not require adenosine triphosphate (ATP) or other cofactors. The light output correlates with the amount of green Renilla protein expressed, which is proportional to the activity of the promoter for green Renilla expression.
Note: Unlike Gaussia and Cypridina, Green Renilla Luciferase can only be assayed in cell lysates as it is not secreted into the cell culture media. Green Renilla luciferase is a ~36 kDa protein.

- Thermo Scientific Pierce Cypridina Luciferase assays provide a highly sensitive system for detecting intracellular and secreted luciferase activity from promoter or pathway activation in mammalian cell culture experiments. The Cypridina luciferase protein is highly secreted into the cell culture media, allowing for live cell monitoring of reporter activity. Cypridina luciferase has greater protein stability and signal brightness than native firefly or Renilla luciferase. The bioluminescent signal produced by Cypridina luciferase results from the oxidation of vargulin. This reaction does not require adenosine triphosphate (ATP) or other cofactors. The light output correlates with the amount of Cypridina protein expressed, which is proportional to the activity of the promoter for Cypridina expression.
Note: Cypridina luciferase is a 61kDa protein.

- Thermo Scientific Pierce Firefly Luciferase Assays provide a highly sensitive system for detecting intracellular luciferase activity from promoter or pathway activation in mammalian cell culture experiments. The bioluminescent signal produced by firefly luciferase results from the oxidation of D-Luciferin. The light output correlates with the amount of firefly protein expressed, which is proportional to the activity of the promoter for firefly expression.
Note: Unlike Gaussia and Cypridina, Firefly Luciferase can only be assayed in cell lysates as it is not secreted into the cell culture media.
Note: Firefly luciferase is a ~60 kDa protein produced in nature by several species of the Lampyridae family of beetles which includes the genera Photinus and Luciola.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

Do you still offer quantitative IP (qIP) Luciferase assay kits?

Our qIP Luciferase assay kits have been discontinued but we do carry epitope-tagged (HA or c-Myc) and Tluc (TurboLuc luciferase)-tagged mammalian expression vectors, and qIP protein interaction assay reagents for these assay kits.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.