giant nuclei is essential in the cell cycle transition from meiosis to mitosis.
نویسندگان
چکیده
At the transition from meiosis to cleavage mitoses, Drosophila requires the cell cycle regulators encoded by the genes, giant nuclei (gnu), plutonium (plu) and pan gu (png). Embryos lacking Gnu protein undergo DNA replication and centrosome proliferation without chromosome condensation or mitotic segregation. We have identified the gnu gene encoding a novel phosphoprotein dephosphorylated by Protein phosphatase 1 at egg activation. Gnu is normally expressed in the nurse cells and oocyte of the ovary and is degraded during the embryonic cleavage mitoses. Ovarian death and sterility result from gnu gain of function. gnu function requires the activity of pan gu and plu.
منابع مشابه
Cdk1 drives meiosis and mitosis through two different mechanisms
Cell cycle progression in mammals involves multiple cyclin-dependent kinases (Cdks). Mice lacking Cdk2, Cdk3, Cdk4 or Cdk6 are viable, however, because Cdk1 can compensate for their loss by forming active complexes with A-, B-, Eand D-type cyclins in a stepwise manner. Thus, these Cdks are not essential for the mammalian cell cycle. In contrast, homozygous deletion of Cdk1 causes early embryoni...
متن کاملCdk1 Modulation Ensures the Coordination of Cell-Cycle Events during the Switch from Meiotic Prophase to Mitosis
BACKGROUND Budding yeast cells that enter the developmental path of meiosis do not commit to finishing meiosis until after prophase I and the realization of such meiosis-specific events as pairing of homologous chromosomes and initiation of recombination. If the meiosis-inducing signal is withdrawn prior to commitment, cells exit meiosis and return to mitosis. The timing of this transition pose...
متن کاملControl of the mitotic exit network during meiosis
The mitotic exit network (MEN) is an essential GTPase signaling pathway that triggers exit from mitosis in budding yeast. We show here that during meiosis, the MEN is dispensable for exit from meiosis I but contributes to the timely exit from meiosis II. Consistent with a role for the MEN during meiosis II, we find that the signaling pathway is active only during meiosis II. Our analysis furthe...
متن کاملPP2A-Twins Is Antagonized by Greatwall and Collaborates with Polo for Cell Cycle Progression and Centrosome Attachment to Nuclei in Drosophila Embryos
Cell division and development are regulated by networks of kinases and phosphatases. In early Drosophila embryogenesis, 13 rapid nuclear divisions take place in a syncytium, requiring fine coordination between cell cycle regulators. The Polo kinase is a conserved, crucial regulator of M-phase. We have recently reported an antagonism between Polo and Greatwall (Gwl), another mitotic kinase, in D...
متن کاملRegulation of maternal transcript destabilization during egg activation in Drosophila.
In animals, the transfer of developmental control from maternal RNAs and proteins to zygotically derived products occurs at the midblastula transition. This is accompanied by the destabilization of a subset of maternal transcripts. In Drosophila, maternal transcript destabilization occurs in the absence of fertilization and requires specific cis-acting instability elements. We show here that eg...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Development
دوره 130 13 شماره
صفحات -
تاریخ انتشار 2003