Question

Some diseases are linked to the under or over expression of specific genes. A particular cancer is characterized by the overexpression of a gene. Do you predict the histones associated with this gene to be acetylated? Describe why this would lead to increased gene expression and how histone acetyl transfer (HAT) and histone deacetylase (HDAC) could be involved.

Answer 1

Overexpression of a gene in cancer is likely associated with acetylation of histones, leading to increased gene expression. Histone acetyl transferases (HATs) add acetyl groups to histones, promoting gene expression, while histone deacetylases (HDACs) remove acetyl groups, leading to gene silencing.

Step-by-step explanation:

In cancer cells, alteration to epigenetic modifications turns off genes that are normally expressed. Specifically, overexpression of a gene in cancer is likely associated with acetylation of histones.

Histone acetylation leads to increased gene expression by loosening the tightly wound DNA, allowing transcription factors and RNA polymerase to access the gene and initiate transcription.

Histone acetyl transferases (HATs) are enzymes that add acetyl groups to histones, promoting gene expression. On the other hand, histone deacetylases (HDACs) remove acetyl groups, leading to gene silencing. In the case of overexpression of a gene in cancer, there would likely be increased histone acetylation due to the activity of HATs and decreased activity of HDACs.