Abstract
Meiotic cells of male mice (spermatocytes) have a very high DNA polymerase-β relative to polymerase-a activity. Similarly, the male meiotic cells of lily have a high ratio of the corresponding DNA polymerases, tentatively designated as B and A. In mice, the ratio is of the order of 50, and in lilies it is about 6. The helix-destabilizing protein of meiotic cells, the "R-protein", specifically stimulates polymerase-β (B) but has no effect on poly-merase-a (A) activity. Mouse R-protein has no effect on lily polymerase-B nor has the lily protein any effect on mouse polymerase-β. Stimulation occurs both in extracts and in isolated nuclei. Dephosphorylated or over-phos-phorylated R-proteins have no stimulatory effect on polymerase activity either in extracts or in isolated nuclei. The high polymerase-β (B) activity in meiotic cells correlates with the endogenously stimulated repair synthesis during meiosis. The interaction between polymerase-β (B) and R-protein may relate to their combined role in meiotic recombination.
