histone /his″tōn/ [Gk, histos, tissue] , any of a group of strongly basic, low-molecular-weight proteins that are soluble in water and insoluble in dilute ammonia and combine with DNA to form nucleoproteins. They are found in the nucleus of eukaryotic cells, where they form a complex with DNA in the chromatin and function in regulating gene activity. See also nucleosome.
