Question

What is the role of histones in compacting DNA

Short answer

Histones serve as spools around which DNA winds and compacts it. They are also involved in controlling which sequence of DNA is turned on for the transcription of RNA.

Step-by-step solution

Histones

Histones possess an important role in the organization and DNA packaging inside the nucleus. They also control gene expression. They create various interaction with DNA like hydrogen bonds, salt bridges etc.

Role of histones in compacting DNA

Histones serve as spools around which DNA winds and compacts it. This forms nucleosomes (length is decreased 8 fold) and look like beads on the string. Complexes are further compacted by a factor of four by a linker histone that binds DNA between the nucleosomes. The compacted molecule is 40,000 times shorter than the unpacked molecule.

Histones are also involved in controlling which sequence of DNA is turned on for the transcription of RNA.