Question

Which of the following are core histones that form part of the histone octamer?

Options

• H2A, H2B, H3, and H4

• H2A, H2B, H3, and H5

• H1, H2A, H2B, and H3

• H1, H3, H4, and H5

Answer 1

The histone octamer consists of eight core histone molecules: two copies each of H2A, H2B, H3, and H4. These four core histone types form the protein core around which 146 base pairs of DNA wrap 1.65 turns to form the nucleosome. H1 is a linker histone not part of the octamer itself.