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EMBO J
1993 Oct 01;1210:4021-7. doi: 10.1002/j.1460-2075.1993.tb06080.x.
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Degradation of Mos by the N-terminal proline (Pro2)-dependent ubiquitin pathway on fertilization of Xenopus eggs: possible significance of natural selection for Pro2 in Mos.
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The c-mos proto-oncogene product (Mos), an essential component of the cytostatic factor responsible for meiotic arrest in vertebrate eggs, undergoes specific proteolysis soon after fertilization or activation of Xenopus eggs. To determine the degradation pathway of Mos on egg activation, various Mos mutants were expressed in Xenopus eggs and their degradation on egg activation was examined. Mos degradation absolutely required its penultimate proline (Pro2) residue and dephosphorylation of the adjacent serine (Ser3) residue. These degradation signals were essentially the same as those of Mos in meiosis I of Xenopus oocyte maturation, where Mos has been shown to be degraded by the 'second-codon rule'-based ubiquitin pathway. To test whether Mos degradation on egg activation is also mediated by the ubiquitin pathway, we attempted to identify and abrogate a specific ubiquitination site(s) in Mos. We show that the major ubiquitination site in Mos is a Lys34 residue and that replacement of this residue with a non-ubiquitinatable Arg residue markedly enhances the stability of Mos on egg activation. These results indicate that the degradation of Mos on egg activation or fertilization is mediated primarily by the N-terminal Pro2-dependent ubiquitin pathway, as in meiosis I of oocyte maturation. The N-terminal Pro2 residue of Mos appears to be naturally selected primarily for its degradation on fertilization, rather than that in meiosis I.
Bachmair,
In vivo half-life of a protein is a function of its amino-terminal residue.
1986, Pubmed
Bachmair,
In vivo half-life of a protein is a function of its amino-terminal residue.
1986,
Pubmed Chau,
A multiubiquitin chain is confined to specific lysine in a targeted short-lived protein.
1989,
Pubmed Dumont,
Oogenesis in Xenopus laevis (Daudin). I. Stages of oocyte development in laboratory maintained animals.
1972,
Pubmed
,
Xenbase Freeman,
Phosphorylation of conserved serine residues does not regulate the ability of mosxe protein kinase to induce oocyte maturation or function as cytostatic factor.
1992,
Pubmed
,
Xenbase Freeman,
Xenopus homolog of the mos protooncogene transforms mammalian fibroblasts and induces maturation of Xenopus oocytes.
1989,
Pubmed
,
Xenbase Gerhart,
Cell cycle dynamics of an M-phase-specific cytoplasmic factor in Xenopus laevis oocytes and eggs.
1984,
Pubmed
,
Xenbase Glotzer,
Cyclin is degraded by the ubiquitin pathway.
1991,
Pubmed
,
Xenbase Goldberg,
Proteolysis, proteasomes and antigen presentation.
1992,
Pubmed Gonda,
Universality and structure of the N-end rule.
1989,
Pubmed Hershko,
Ubiquitin-mediated protein degradation.
1988,
Pubmed Kawahara,
The 26 S proteasome is activated at two points in the ascidian cell cycle.
1992,
Pubmed Lorca,
Degradation of the proto-oncogene product p39mos is not necessary for cyclin proteolysis and exit from meiotic metaphase: requirement for a Ca(2+)-calmodulin dependent event.
1991,
Pubmed
,
Xenbase Masui,
Cytoplasmic control of nuclear behavior during meiotic maturation of frog oocytes.
1971,
Pubmed Masui,
Oocyte maturation.
1979,
Pubmed Newport,
Regulation of the cell cycle during early Xenopus development.
1984,
Pubmed
,
Xenbase Nishizawa,
The 'second-codon rule' and autophosphorylation govern the stability and activity of Mos during the meiotic cell cycle in Xenopus oocytes.
1992,
Pubmed
,
Xenbase Okazaki,
Differential occurrence of CSF-like activity and transforming activity of Mos during the cell cycle in fibroblasts.
1992,
Pubmed
,
Xenbase Orlowski,
The multicatalytic proteinase complex, a major extralysosomal proteolytic system.
1990,
Pubmed Rechsteiner,
Ubiquitin-mediated pathways for intracellular proteolysis.
1987,
Pubmed Reiss,
Specificity of binding of NH2-terminal residue of proteins to ubiquitin-protein ligase. Use of amino acid derivatives to characterize specific binding sites.
1988,
Pubmed Sagata,
The c-mos proto-oncogene product is a cytostatic factor responsible for meiotic arrest in vertebrate eggs.
1989,
Pubmed
,
Xenbase Sagata,
The product of the mos proto-oncogene as a candidate "initiator" for oocyte maturation.
1989,
Pubmed
,
Xenbase Sagata,
Function of c-mos proto-oncogene product in meiotic maturation in Xenopus oocytes.
1988,
Pubmed
,
Xenbase Schimke,
Control of enzyme levels in animal tissues.
1970,
Pubmed Shibuya,
Stabilization and enhancement of primary cytostatic factor (CSF) by ATP and NaF in amphibian egg cytosols.
1988,
Pubmed
,
Xenbase Taylor,
The rapid generation of oligonucleotide-directed mutations at high frequency using phosphorothioate-modified DNA.
1985,
Pubmed Varshavsky,
The N-end rule.
1992,
Pubmed Watanabe,
Independent inactivation of MPF and cytostatic factor (Mos) upon fertilization of Xenopus eggs.
1991,
Pubmed
,
Xenbase Watanabe,
Specific proteolysis of the c-mos proto-oncogene product by calpain on fertilization of Xenopus eggs.
1989,
Pubmed
,
Xenbase