Influence of a specific histone kinase on the physico-chemical properties of chromatin in situ.

The influence of a specific histone kinase, phosphorylating lysine-rich histone F1, F2a2, F2b, on the physico-chemical properties of the chromatin in the whole undestroyed fixed cell, has been investigated. It was found that the exogenous histone kinase penetrates into the nuclei of the undestroyed fixed cells and into the isolated unfixed nuclei and changes the physico-chemical properties of the chromatin there, bringing about an increase in binding of a basic dye acridine orange and a decrease in its stability to heat.