ATP-γ-S (adenosine 5′-O-(3-thiotriphosphate)) microinjection increases progesterone-stimulated histone kinase activity in Xenopus oocytes

Abstract

Progesterone stimulates the activity of a potent Ca²⁺- and cyclic nucleotide-independent histone kinase in Xenopus oocytes. Microinjection of ATP-γ-S during the course of meiotic maturation or after the oocytes had arrested at second meiotic metaphase resulted in a further increase of this histone kinase activity in progesterone-stimulated oocytes. ATP-γ-S microinjection also increased and stabilized the activity of the maturation-promoting factor. The possible mechanism of ATP-γ-S action is discussed.