Question

The following enzyme will increase gene expression

1) histone acetytransferase

2) DNA methylation

3) telomerase

4)histone deacetylation

Answer 1

Histone acetyltransferase add acetyl group over lysine and arginine on the N terminal of histone. Normally both the amino acids bear positive charges, bind with DNA(charge negative) very tightly so formation of heterochromatin occurs. As acetyl groups are added difference comes in the charge of amino acid and they no more bind tightly with DNA and becomes loosely bound called euchromatin structure. Thus expression of gene increases as euchromatin represents major genes and is transcriptionally active form.