Reporter genes have become an invaluable tool in studies of gene expression. They are widely used in biomedical and pharmaceutical research and also in molecular biology and biochemistry.

A gene consists of two functional parts: One is a DNA-sequence that gives the information about the protein that is produced (coding region). The other part is a specific DNA-sequence linked to the coding region; it regulates the transcription of the gene (promoter). The promoter is either activating or suppressing the expression of the gene.

The purpose of the reporter gene assay is to measure the regulatory potential of an unknown DNA-sequence. This can be done by linking a promoter sequence to an easily detectable reporter gene such as that encoding for the firefly luciferase.

Common reporter genes are β-galactosidase, β-glucuronidase and luciferase. Various detection methods (see below) are used to measure expressed reporter gene protein. These include luminescence, absorbance and fluorescence.

Reporter	Detection Method
	Luminescence     Fluorescence    Absorbance
Luciferase	+	+
β-Galactosidase (GUS)	+	+	+
β-Glucuronidase (b-Gal)	+	+
Secreted placental alkaline phosphatase (SEAP)	+		+
Green Fluorescent Protein (GFP)		+

Luciferase Reporter Gene Assay

The advantages of a luciferase assay are the high sensitivity, the absence of luciferase activity inside most of the cell types, the wide dynamic range, rapidity and low costs.

The most versatile and common reporter gene is the luciferase of the North American firefly Photinus pyralis. The protein requires no posttranslational modification for enzyme activity; it is not even toxic in high concentration (in vivo) and can be used in pro- and eukaryotic cells.

The firefly luciferase catalyzes the bioluminescent oxidation of the luciferin in the presence of ATP, Magnesium and Oxygen:

Dual Luciferase^TM Reporter Gene Assay

The Dual-Luciferase^TM Reporter (DLR) Assay System contains two different luciferase reporter enzymes that are expressed simultaneously in each cell. The firefly luciferase and the Renilla (sea pansy) luciferase can discriminate between their respective bioluminescence substrates and do not cross-activate.

Validated DLReady^TM the Berthold instruments Mithras LB 940, Centro LB 960 and Lumat LB 9507 are ideally suited for this type of reporter gene assay. The instruments´ software MikroWin contains predefined DLR parameter files ready to use.

DLR and DLReady logo are trademarks of Promega Corporation.

Dual Luciferase Assay Kits from Interchim

• Linear correlation between luciferase gene and light
  output for transfection using 0.001 µg to 1µg DNA of either Firefly or Renilla luciferase reporter constructs
• Reduced autoluminescence background for Renilla luciferase
• Increased sensitivity

Firefly & Renilla Luciferase Assay Kit (100 tests)           FP-BE7810
Firefly & Renilla Luciferase Assay Kit (1000 tests)         FP-BE7811
Renilla Luciferase Assay Kit (150 tests)                       FP-BE7930
Firefly Luciferase Assay Kit (150 tests)                       FP-BE7940
D-Luciferin, Na salt (25 mg)                                      FP-72604A
Coelenterazine native (1 mg)                                    UP972333