Question

Which statement about reporters is false?

A. Lab-worthy GFP emits a green fluorescence when it binds and cleaves its substrate when illuminated with UV light.
B. Luciferase enzymes use luciferin substrates to yield a light (photon) signal; they are often used to measure promoter activity.
C. Beta-galactosidase is an enzyme encoded by the lacZ gene and cleaves galactosides like ONPG and X-gal to yield yellow and blue colors, respectively.
D. Alkaline phosphatase is an enzyme encoded by the phoA gene that cleaves ONPP to yield a yellow color and XP to yield blue.

Answer 1

The false statement about reporters is that GFP emits green fluorescence when it binds and cleaves a substrate; it actually fluoresces green without substrate cleavage.

Step-by-step explanation:

The statement about reporters that is false is: "Lab-worthy GFP emits a green fluorescence when it binds and cleaves its substrate when illuminated with UV light." In fact, GFP (Green Fluorescent Protein) does not require binding and cleaving a substrate to emit green fluorescence; it inherently fluoresces green when illuminated with UV light. The correct descriptions of reporter genes and enzymes include:

• Luciferase enzymes use luciferin substrates to yield a light (photon) signal and are often used to measure promoter activity.
• Beta-galactosidase, encoded by the lacZ gene, cleaves galactosides like ONPG and X-gal to yield yellow and blue colors, respectively.
• Alkaline phosphatase, encoded by the phoA gene, cleaves substrates such as ONPP to yield yellow color, but it does not produce a blue color when cleaving XP.

As a reporters, GFP, beta-galactosidase, and alkaline phosphatase serve important functions in biochemical assays and gene expression studies.