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Proc Natl Acad Sci U S A
2005 Mar 22;10212:4318-23. doi: 10.1073/pnas.0501108102.
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A role for the anaphase-promoting complex inhibitor Emi2/XErp1, a homolog of early mitotic inhibitor 1, in cytostatic factor arrest of Xenopus eggs.
Tung JJ
,
Hansen DV
,
Ban KH
,
Loktev AV
,
Summers MK
,
Adler JR
,
Jackson PK
.
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Unfertilized vertebrate eggs are arrested in metaphase of meiosis II with high cyclin B/Cdc2 activity to prevent parthenogenesis. Until fertilization, exit from metaphase is blocked by an activity called cytostatic factor (CSF), which stabilizes cyclin B by inhibiting the anaphase-promoting complex (APC) ubiquitin ligase. The APC inhibitor early mitotic inhibitor 1 (Emi1) was recently found to be required for maintenance of CSF arrest. We show here that exogenous Emi1 is unstable in CSF-arrested Xenopus eggs and is destroyed by the SCF(betaTrCP) ubiquitin ligase, suggesting that endogenous Emi1, an apparent 44-kDa protein, requires a stabilizing factor. However, anti-Emi1 antibodies crossreact with native Emi2/Erp1/FBXO43, a homolog of Emi1 and conserved APC inhibitor. Emi2 is stable in CSF-arrested eggs, is sufficient to prevent CSF release, and is rapidly degraded in a Polo-like kinase 1-dependent manner in response to calcium-mediated egg activation. These results identify Emi2 as a candidate CSF maintenance protein.
Bhatt,
The protein kinase p90 rsk as an essential mediator of cytostatic factor activity.
1999, Pubmed,
Xenbase
Bhatt,
The protein kinase p90 rsk as an essential mediator of cytostatic factor activity.
1999,
Pubmed
,
Xenbase
Descombes,
The polo-like kinase Plx1 is required for M phase exit and destruction of mitotic regulators in Xenopus egg extracts.
1998,
Pubmed
,
Xenbase
Ferrell,
Xenopus oocyte maturation: new lessons from a good egg.
1999,
Pubmed
,
Xenbase
Furuno,
Suppression of DNA replication via Mos function during meiotic divisions in Xenopus oocytes.
1994,
Pubmed
,
Xenbase
Gautier,
Purified maturation-promoting factor contains the product of a Xenopus homolog of the fission yeast cell cycle control gene cdc2+.
1988,
Pubmed
,
Xenbase
Gautier,
Cyclin is a component of maturation-promoting factor from Xenopus.
1990,
Pubmed
,
Xenbase
Guardavaccaro,
Control of meiotic and mitotic progression by the F box protein beta-Trcp1 in vivo.
2003,
Pubmed
Hansen,
Plk1 regulates activation of the anaphase promoting complex by phosphorylating and triggering SCFbetaTrCP-dependent destruction of the APC Inhibitor Emi1.
2004,
Pubmed
,
Xenbase
Hochegger,
New B-type cyclin synthesis is required between meiosis I and II during Xenopus oocyte maturation.
2001,
Pubmed
,
Xenbase
Howe,
Identification of a developmental timer regulating the stability of embryonic cyclin A and a new somatic A-type cyclin at gastrulation.
1995,
Pubmed
,
Xenbase
Hsu,
E2F-dependent accumulation of hEmi1 regulates S phase entry by inhibiting APC(Cdh1).
2002,
Pubmed
,
Xenbase
Jin,
Systematic analysis and nomenclature of mammalian F-box proteins.
2004,
Pubmed
King,
A 20S complex containing CDC27 and CDC16 catalyzes the mitosis-specific conjugation of ubiquitin to cyclin B.
1995,
Pubmed
,
Xenbase
Margottin-Goguet,
Prophase destruction of Emi1 by the SCF(betaTrCP/Slimb) ubiquitin ligase activates the anaphase promoting complex to allow progression beyond prometaphase.
2003,
Pubmed
,
Xenbase
Masui,
Cytoplasmic control of nuclear behavior during meiotic maturation of frog oocytes.
1971,
Pubmed
Minshull,
Xenopus oocyte maturation does not require new cyclin synthesis.
1991,
Pubmed
,
Xenbase
Moshe,
Role of Polo-like kinase in the degradation of early mitotic inhibitor 1, a regulator of the anaphase promoting complex/cyclosome.
2004,
Pubmed
,
Xenbase
Murray,
The role of cyclin synthesis and degradation in the control of maturation promoting factor activity.
1989,
Pubmed
,
Xenbase
Ohsumi,
Emi1-mediated M-phase arrest in Xenopus eggs is distinct from cytostatic factor arrest.
2004,
Pubmed
,
Xenbase
Paronetto,
Functional interaction between p90Rsk2 and Emi1 contributes to the metaphase arrest of mouse oocytes.
2004,
Pubmed
Reimann,
Emi1 regulates the anaphase-promoting complex by a different mechanism than Mad2 proteins.
2001,
Pubmed
,
Xenbase
Reimann,
Emi1 is required for cytostatic factor arrest in vertebrate eggs.
2002,
Pubmed
,
Xenbase
Reimann,
Emi1 is a mitotic regulator that interacts with Cdc20 and inhibits the anaphase promoting complex.
2001,
Pubmed
,
Xenbase
Sagata,
The c-mos proto-oncogene product is a cytostatic factor responsible for meiotic arrest in vertebrate eggs.
1989,
Pubmed
,
Xenbase
Tung,
Emi1 class of proteins regulate entry into meiosis and the meiosis I to meiosis II transition in Xenopus oocytes.
2005,
Pubmed
,
Xenbase
Tunquist,
The spindle checkpoint kinase bub1 and cyclin e/cdk2 both contribute to the establishment of meiotic metaphase arrest by cytostatic factor.
2002,
Pubmed
,
Xenbase
Tunquist,
Under arrest: cytostatic factor (CSF)-mediated metaphase arrest in vertebrate eggs.
2003,
Pubmed
,
Xenbase
