The cyclic behavior of a cytoplasmic factor controlling nuclear membrane breakdown

The activity of a cytoplasmic factor (MPF), capable of inducing nuclear membrane breakdown (germinal vesicle breakdown) when injected into amphibian oocytes, has been studied during the course of early cleavage in amphibian embryos. Mature egg cytoplasm was found to contain high levels of this activity, but this was quickly lost after fertilization or artificial activation. MPF activity later reappeared in the egg cytoplasm and started to cycle with time. The peak of embryonic MPF activity during each cycle coincided with the time the embryonic nuclei were entering the G2-M transition, i.e., mitosis. However, in colchicine-arrested embryos, this activity remained at an elevated level and no longer oscillated. The timing of the appearance and disappearance of this activity appeared to be under the control of the cytoplasm because such behavior was still observed in enucleated eggs. Continued protein synthesis in the embryo was required for the reappearance, but not for the disappearance, of this activity. MPF, previously thought to be restricted to oocyte maturation, may play a more general role in controlling nuclear membrane breakdown during mitosis as well as meiosis.

[1]  V. Hamburger.  A Manual Of Experimental Embryology , 1942 .

[2]  K. R. Porter.  ANDROGENETIC DEVELOPMENT OF THE EGG OF RANA PIPIENS , 1939 .

[3]  Y. Masui,et al.  Control of chromosome behavior in amphibian oocytes. I. The activity of maturing oocytes inducing chromosome condensation in transplanted brain nuclei. , 1973, Developmental biology.

[4]  T. Kishimoto,et al.  Cytoplasmic factor responsible for germinal vesicle breakdown and meiotic maturation in starfish oocyte , 1976, Nature.

[5]  W. Hittelman,et al.  Mammalian cell fusion: VI. Regulation of mitosis in binucleate HeLa cells , 1975 .

[6]  A. Sandberg,et al.  INDUCTION OF NUCLEAR ENVELOPES AROUND METAPHASE CHROMOSOMES AFTER FUSION WITH INTERPHASE CELLS , 1971, The Journal of cell biology.

[7]  K. Drury,et al.  Progesterone induced maturation in oocytes of Xenopus laevis. Appearance of a 'maturation promoting factor' in enucleated oocytes. , 1973, Cell differentiation.

[8]  Robert T. Johnson,et al.  Mammalian Cell Fusion : Studies on the Regulation of DNA Synthesis and Mitosis , 1970, Nature.

[9]  Y. Masui,et al.  A study on gonadotropin action in the induction of oocyte maturation in Xenopus laevis. , 1974, Biology of reproduction.

[10]  Y. Masui,et al.  A cytoplasmic factor promoting oocyte maturation: its extraction and preliminary characterization. , 1976, Science.

[11]  J. Hedrick,et al.  A molecular approach to fertilization. I. Disulfide bonds in Xenopus laevis jelly coat and a molecular hypothesis for fertilization. , 1971, Developmental biology.

[12]  S. Subtelny,et al.  Cytological observations on the early developmental stages of activated Rana pipiens eggs receiving a transplanted blastula nucleus , 1963, Journal of morphology.

[13]  J. Gurdon,et al.  Changes in somatic cell nuclei inserted into growing and maturing amphibian oocytes. , 1968, Journal of embryology and experimental morphology.

[14]  Y. Masui,et al.  Effects of cyclohexamide on a cytoplasmic factor initiating meiotic naturation in Xenopus oocytes. , 1975, Experimental cell research.

[15]  J. Reynhout,et al.  Studies on the appearance and nature of a maturation-inducing factor in the cytoplasm of amphibian oocytes exposed to progesterone. , 1974, Developmental biology.

[16]  D. Prescott,et al.  Nuclear-Cytoplasmic Interaction in DNA Synthesis , 1967, Science.

[17]  L. D. Smith,et al.  The interaction of steroids with Rana pipiens Oocytes in the induction of maturation. , 1971, Developmental biology.

[18]  N. de Terra.  MACRONUCLEAR DNA SYNTHESIS IN Stentor: REGULATION BY A CYTOPLASMIC INITIATOR. , 1967, Proceedings of the National Academy of Sciences of the United States of America.

[19]  P. N. Rao,et al.  Mammalian Cell Fusion : Induction of Premature Chromosome Condensation in Interphase Nuclei , 1970, Nature.

[20]  C. Markert,et al.  Cytoplasmic control of nuclear behavior during meiotic maturation of frog oocytes. , 1971, The Journal of experimental zoology.

[21]  C. Graham.  The regulation of DNA synthesis and mitosis in multinucleate frog eggs. , 1966, Journal of cell science.

[22]  R. Wallace,et al.  Protein incorporation by isolated amphibian oocytes. I. Preliminary studies. , 1970, The Journal of experimental zoology.

[23]  R. Czołowska,et al.  Cytoplasmic control of nuclear maturation in mouse oocytes. , 1977, Experimental cell research.