Promoter-reporter+fusions

=Promoter-reporter fusion=

A **promoter-reporter fusion** is a technique used to determine the DNA sequences within a promoter region that are responsible for regulating transcription. The promoter region of interest is fused to a **reporter gene**: a gene that codes for a protein product that can easily be detected, such as a fluorescent protein.

The general method of promoter-reporter fusion is:

1. Clone the gene containing the promoter region that you want to examine; 2. Cut the cloned gene into fragments with a suitable restriction enzyme; 3. Ligate the promoter into a plasmid containing a promoter-less reporter gene; 4. Use the recombinant plasmids to transform a suitable host; 5. Assay the transformants for reporter gene activity.

By performing a series of deletions on the promoter region, and observing reporter gene activity, it is possible to determine precisely which DNA sequences are needed to regulate transcription of the gene.