[Identification of myosin-like proteins included in chromatin].

A myosin-like protein was purified 40-fold from rat liver chromatin (as determined by the K+-EDTA-ATPase activity equal to 0.013 and 0.442 M PPi/mg.min for chromatin and purified protein, respectively). Electrophoresis performed under non-denaturating conditions revealed that the overall ATPase activity of the sample is associated with one component whose migration is very similar to that of skeletal muscle myosin. The myosin components isolated from the nuclei and cytoplasm of rat cardiac muscle differ by their electrophoretic mobilities; those from nuclei of different tissues, i.e., liver and heart, have similar mobilities.