[Biological effects of solutions of non-histone chromatin-associated proteins on cell differentiation in vitro (author's transl)].

Nuclear non-histone (NNH) proteins, both chromatin-associated and otherwise, have been prepared in defined conditions, either from nuclei or from washed chromatin. When these NNH proteins are homospecific, they produce inhibitory effects on morphological differentiation of embryonic Urodelan Amphibian cells cultivated in vitro. When they are heterospecific, on the contrary, they have no action on the differentiation of those cells. It is concluded that the effects of the non-histone proteins on cell differentiation depend upon the relationship between the animal species which is used to provide the proteins and that used to provide the reactive material.