Abstract
The histone H10 was examined from 7 mammalian species [rabbit, mouse, rat, hamster, human, porcine, bovine]. All tissues contained 2 subfractions of H10, except for those of rabbit, in which little or no H10 was found. The subfraction composition was compared quantitatively in different mouse and hamster tissues, with the conclusion that this composition is tissue-specific. It is proposed that the wide occurrence of H10, together with the evidence of no more or less than 2 subfractions wherever it occurs, and the tissue-specific nature of the ratio of subfractions, signify that these 2 subfractions have specific individual functions.