Question

How were core promoter elements identified?

Answer 1

Core promoter are the regions in the DNA where the RNA polymerase binds to start the transcription. They are usually -35 to -10 base pairs upstream of the gene. The most widely known core promoter is the TATA box in eukaryotes and Pribnow box in bacteria. They serve as a start site of the transcription and also helps in gene regulation.

A great variety of algorithms have been generated for prediction of promoters by gene prediction methods(in silico). Earlier promoter regions were identified by in vitro lab experiments which included-

1- Isolation of target gene by help of restriction digestion

2-Sequencing of the gene by use of Sanger sequencing.

3- Developing of the consensus sequence for that promoter region in the same species by alignment.

Nowadays new methods like Laser tweezers have been developed by which the relative postion of the promoters can be identified easily.