[Isolation of actomyosin from a skeletal muscle tumor of low differentiation]

A method of actomyosin (AM) isolation from low-differentiated rhabdomyocarcoma (LD RMS) has been worked out. The preparations obtained are sufficiently pure to be used for determination of the composition and some properties of major contractile proteins. Data on the composition of AM preparations isolated from LD RMS by traditional muscular biochemical methods (Matveyev, 1984) and morphological peculiarities of LD RMS cells, which help to distinguish them from definitive skeletal muscle cells and to relate them to non-muscle and low-differentiated muscle cells (mitotic myoblasts), served the main prerequisite to developing the method. Thus, this method may be regarded as a rational basis for isolation of non-muscle and embryonic contractile proteins, but it can be used, probably, for such purposes without special any adjustment to non-muscle or embryonic cells. The cytoplasmic localization has been shown for the tumor myosin.