A class of basic proteins associated with
DNA in the chromosomes of eukaryotic cells forming the nucleosome as the basic subunit of chromatin. They contain an unusually large proportion of the basic amino acids arginine and lysine.
Source:
PAC, 1992, 64, 143. 'Glossary for chemists of terms used in biotechnology (IUPAC Recommendations 1992)' on page 156 (https://doi.org/10.1351/pac199264010143)