title: Expression of specific genes in early mouse embryos blocked by cytochalasin.
abstract: Mouse embryos at the two cell stage derived from C57BL/6 × C3H/Aa F1-females heterozygous at the X-linked phosphoglycerate kinase locus (Pgk-1) were cultured continuously in the presence of cytochalasin B or D. Further cleavage of the two cell embryos was thus prevented and the embryos became polyploid during culture. The onset of expression of the maternally inherited Pgk-1 gene and of the paternally inherited glucosephosphate isomerase (Gpi-1) gene was determined in these polyploid embryos by cellulose acetate gel electrophoresis of single embryos. In contrast to euploid preimplantation embryos developing normally in utero or in culture without cytochalasins, expression of maternal Pgk-1 was never observed at days 4 and 5 of gestation in polyploid two cell embryos, showing that the Pgk-1 allele on the maternally inherited X chromosome is not activated independently of cytokinesis and morphogenesis. Expression of paternally derived Gpi-1, however, occurred in cleavage blocked embryos von day 5 of development. This may indicate that the activation of two genes which are both expressed during preimplantation development and which both code for glycolytic enzymes, is initiated by different signals.
authors.affiliation: Laboratoire de Différenciation Cellulaire, Ecole de Médecine, 20, rue de l'Ecole-de-Médecine, CH-1211, Genève 4.
authors.forename: Reinald
authors.initials: R
authors.lastname: Fundele
authors.affiliation: Laboratoire de Différenciation Cellulaire, Ecole de Médecine, 20, rue de l'Ecole-de-Médecine, CH-1211, Genève 4.
authors.forename: Karl
authors.initials: K
authors.lastname: Illmensee
authors.affiliation: Laboratoire de Différenciation Cellulaire, Ecole de Médecine, 20, rue de l'Ecole-de-Médecine, CH-1211, Genève 4.
authors.forename: Eva -Maria
authors.initials: E-
authors.lastname: Jägerbauer
authors.affiliation: Institut für Physiologische Chemie, Physikalische Biochemie und Zellbiologie, Goethestraße 33, D-8000, München 2, Federal Republic of Germany.
authors.forename: Monika
authors.initials: M
authors.lastname: Fehlau
authors.affiliation: Institut für Physiologische Chemie, Physikalische Biochemie und Zellbiologie, Goethestraße 33, D-8000, München 2, Federal Republic of Germany.
authors.forename: Wolfgang K G
authors.initials: WK
authors.lastname: Krietsch
keywords: Cytochalasin; Glucosephosphate isomerase; Mouse embryogenesis; Phosphoglycerate kinase