Question

What is a histone variant?

Short answer

A histone variant is a protein that differs in sequence from the standard histone proteins that package DNA into chromatin. These variants often have different structures and are involved in critical biological processes such as gene expression regulation, DNA repair, and chromatin structure stabilization.

Step-by-step solution

Definition

A histone variant is a protein that differs in sequence from the standard histone proteins (H2A, H2B, H3, H4) that usually package DNA into chromatin in eukaryotic cells.

Structural Difference

Histone variants often have different structures than standard histones. These minor differences in sequence can lead to significant changes in the structure and stability of the chromatin.

Functional Role

Histone variants also play critical roles in a variety of biological processes. They are involved in the regulation of gene expression, DNA repair, and chromatin structure stabilization among other functions.