Initiation of Cyclin B Degradation by the 26S Proteasome upon Egg Activation
Toshinobu Tokumoto,Masakane Yamashita,Mika Tokumoto,Yoshinao Katsu,Ryo Horiguchi,Hiroko Kajiura,Yoshitaka Nagahama +6 more
Reads0
Chats0
TLDR
The results of this study indicate that Mutant cyclin at K57 was resistant to both digestion by the 26S proteasome and degradation at metaphase/anaphase transition in Xenopus egg extracts, indicating that the destruction of cyclin B is initiated by the ATP-dependent and ubiquitin-independent proteolytic activity of 26S Proteasome through the first cutting in the NH2 terminus ofcyclin.Abstract:
Immediately before the transition from metaphase to anaphase, the protein kinase activity of maturation or M-phase promoting factor (MPF) is inactivated by a mechanism that involves the degradation of its regulatory subunit, cyclin B. The availability of biologically active goldfish cyclin B produced in Escherichia coli and purified goldfish proteasomes (a nonlysosomal large protease) has allowed the role of proteasomes in the regulation of cyclin degradation to be examined for the first time. The 26S, but not the 20S proteasome, digested recombinant 49-kD cyclin B at lysine 57 (K57), producing a 42-kD truncated form. The 42-kD cyclin was also produced by the digestion of native cyclin B forming a complex with cdc2, a catalytic subunit of MPF, and a fragment transiently appeared during cyclin degradation when eggs were released from metaphase II arrest by egg activation. Mutant cyclin at K57 was resistant to both digestion by the 26S proteasome and degradation at metaphase/anaphase transition in Xenopus egg extracts. The results of this study indicate that the destruction of cyclin B is initiated by the ATP-dependent and ubiquitin-independent proteolytic activity of 26S proteasome through the first cutting in the NH2 terminus of cyclin (at K57 in the case of goldfish cyclin B). We also surmise that this cut allows the cyclin to be ubiquitinated for further destruction by ubiquitin-dependent activity of the 26S proteasome that leads to MPF inactivation.read more
Citations
More filters
Journal ArticleDOI
Regulation of oocyte maturation in fish.
TL;DR: This article showed that oocyte maturation is a three-step induction process involving gonadotropin (LH), maturation-inducing hormone (MIH), and maturationpromoting factor (MPF).
Journal ArticleDOI
Down-regulation of p27 Kip1 by Two Mechanisms, Ubiquitin-mediated Degradation and Proteolytic Processing
Michiko Shirane,Yumiko Harumiya,Noriko Ishida,Aizan Hirai,Chikara Miyamoto,Shigetsugu Hatakeyama,Keiichi I. Nakayama,Masatoshi Kitagawa +7 more
TL;DR: This study demonstrated that two posttranslational mechanisms were involved in p27 Kip1 breakdown: degradation via the ubiquitin (Ub)-proteasome pathway and proteolytic processing that rapidly eliminates the cyclin-binding domain.
Journal ArticleDOI
Cell-Free Degradation of p27 kip1 , a G1 Cyclin-Dependent Kinase Inhibitor, Is Dependent on CDK2 Activity and the Proteasome
TL;DR: A cell-free degradation system is defined which faithfully recapitulates the cell cycle phase-specific degradation of p27, and it is shown that this reaction is dependent on active CDK2 activity, suggesting that CDK 2 activity is directly required for p27 degradation.
Journal ArticleDOI
The proteasome is involved in the first metaphase-to-anaphase transition of meiosis in rat oocytes.
TL;DR: It is demonstrated that proteasomal catalytic activity is absolutely essential for the decrease in MPF activity and completion of the first meiotic division, which may facilitate the timely degradation of cyclin B.
Journal ArticleDOI
Degradation of the G Protein-coupled Receptor Kinase 2 by the Proteasome Pathway *
TL;DR: It is shown that GRK2 is actively degraded by the proteasome proteolytic pathway, unveiling a new mechanism for the rapid regulation of its expression levels and revealing an important mechanism for modulating the cellular response to agonists acting through G protein-coupled receptors.
References
More filters
Journal ArticleDOI
Cleavage of Structural Proteins during the Assembly of the Head of Bacteriophage T4
TL;DR: Using an improved method of gel electrophoresis, many hitherto unknown proteins have been found in bacteriophage T4 and some of these have been identified with specific gene products.
Journal Article
Cleavage of structural proteins during the assemble of the head of bacterio-phage T4
TL;DR: Using an improved method of gel electrophoresis, many hitherto unknown proteins have been found in bacteriophage T4 and some of these have been identified with specific gene products as mentioned in this paper.
Journal ArticleDOI
Rapid and efficient site-specific mutagenesis without phenotypic selection.
TL;DR: The high efficiency, approximately equal to 10-fold greater than that observed using current methods without enrichment procedures, is obtained by using a DNA template containing several uracil residues in place of thymine, which is applied to mutations introduced via both oligonucleotides and error-prone polymerization.
Journal ArticleDOI
Inhibitors of the proteasome block the degradation of most cell proteins and the generation of peptides presented on MHC class I molecules
Kenneth L. Rock,Colette F. Gramm,Lisa Rothstein,Karen Clark,Ross L. Stein,Lawrence Dick,Daniel Hwang,Alfred L. Goldberg +7 more
TL;DR: Peptide aldehydes that inhibit major peptidase activities of the 20S and 26S proteasomes are shown to reduce the degradation of protein and ubiquitinated protein substrates by 26S particles.
Journal ArticleDOI
Cyclin is degraded by the ubiquitin pathway
TL;DR: Cyclin degradation is the key step governing exit from mitosis and progress into the next cell cycle, and anaphase may be triggered by the recognition of cyclin by the ubiquitin-conjugating system.