[Protein composition and electron microscopy of the residual protein fractions of cell nuclei of certain normal organs and tumors of rats].

A marked difference in polypeptide pattern and electron micrographs of the nuclear residual protein fraction between normal tissues /liver, kidney, spleen/ and tumors /hepatoma 27, Jensen and Yoshida sarcomas/ is revealed. While in normal tissues the polypeptides with molecular weight lower than 26 KD constituted about one half of the total residual protein, in tumors the polypeptides with molecular weight exceeding 100 KD were markedly prevailing. In electron micrographs the uniform filaments with a diameter of 4-5 nm, and periodical structure represented the bulk of the preparation from normal liver, while in the case of hepatoma 27 an amorphous granulated material was predominating.