[Demonstration of maturation promoting factor activity in Saccharomyces cerevisiae]. / Mise en évidence d'une activité "MPF" chez Saccharomyces cerevisiae.

Microinjection of a crude yeast extract into fully grown immature Xenopus laevis oocytes induces the reinitiation of meiotic maturation as does Xenopus laevis oocyte MPF (Maturation Promoting Factor) by itself. Using several strains of yeast exhibiting temperature sensitive cell cycle block (cdc), it was observed that yeast extract exhibits MPF activity only when obtained during the time interval from the G2 period to the metaphase. This observation stresses eucaryotic ubiquity of MPF.