Anonymous ID: c7db66 Dec. 18, 2022, 1:22 a.m. No.17976417   🗄️.is đź”—kun

>>17974780

There are many ways that a cell can regulate if and when a gene gets read. For now, we’re going to focus on a very common method which involves transcription factors and promoters. Promoters are stretches of DNA that can be recognized by a class of proteins known as transcription factors. These proteins interact with the DNA to orchestrate transcription (or block them from getting started). To put it more simply, transcription factors help draw attention to, or away from, certain genes.

As the starting point for every gene, the promoter is a natural place to control how much (or how little) a gene is read. To this end, promoters are often the target of multiple regulatory processes. A single promoter may be recognized by numerous transcription factors, each of which serves a different role in regulating the nearby gene—like controlling the gene in a time- or location-specific manner.

 

The relationship between a promoter and its transcription factors is a diverse and efficient method of regulation. Consider that a specific portion of a promoter may attract repressive transcription factors that effectively prevent a gene from being transcribed, or it can attract activating transcription factors that increase a gene’s usage. How the gene is regulated depends on which transcription factors are able to interact with the promoter.

 

To boil it down, here’s what we’ve covered so far:

 

Genes have instructions for building proteins.

Polymerases are proteins that simply copy DNA sequences into RNA.

Transcription factors help tell the polymerases what segments of DNA to read.

Promoters help transcription factors know which genes to regulate.

 

https://blog.helix.com/2018/03/decides-dna-read-cells/