Occurrence of the Low-Mobility H1 Histone Subfraction in Embryonic, Differentiated, and Neoplastic Tissues of the Syrian Hamster

Electrophoretically slow H1 histone subfractions with mobilities identical to that of the subfraction found in the Kirkman-Robbins hamster hepatoma chromatin have been shown to be present in 12-day hamster embryos and in a sarcoma-type hamster tumor induced by SV40. A suggestion is made that some defective mechanisms of differentiation may affect the regulation of expression of the genes coding for the H1 histone subfractions. The same mechanisms may possible but not necessarily be connected with the molecular events leading to neoplastic growth.