Relationship of single-stranded DNA-binding proteins of Ehrlich ascites tumour to cell growth phase and DNA replications.

The possible involvement of SSB-proteins in DNA replication in Ehrlich ascites tumour (EAT) has been investigated. A direct relation (the computer-generated correlation coefficient was 0.9) between the SSB-proteins content in chromatin and intensity of the replicative synthesis of DNA in various preparation of EAT in vivo and in vitro is observed. Addition of exogenous SSB-proteins to the permeable EAT cells has been found to increase the replicative synthesis. Although eukaryotic SSB-proteins are not complete analogs of the prokaryotic SSB-proteins, they evidently participate in DNA replication in eukaryotic cells and possibly are intracellular regulators of proliferation.