Question

Why do Archaea have no tails on their histones H3 and H4?

- The tails are located on histone H2A and H2B in the Archaea.
-Archaeal histone H1 serves this role.
- Since the nucleosome is a tetramer, there is no room for tails in the structure.
-They do not need to clamp the nucleosome onto the DNA very tightly.
-They only form the 10 nm fiber, so there is no need for the histone code (which is located on the tails) to signal the condensation of chromatin.

Answer 1

Archaea have no tails on their histones H3 and H4 due to the structure of the nucleosomes and the specific needs of Archaea in DNA packaging. The tails are located on other histone proteins in Archaea, mainly histone H2A and H2B.

Step-by-step explanation:

Archaea have no tails on their histones H3 and H4 because the tails are located on histone H2A and H2B in Archaea. Archaeal histone H1 serves the role of the tails in other organisms. The reason there are no tails on H3 and H4 is because the nucleosome structure, which is formed by histones wrapping DNA, consists of a tetramer, leaving no room for tails. Also, Archaea only form the 10 nm fiber, so there is no need for the histone code (which is located on the tails) to signal the condensation of chromatin.