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SCF-Fbxo42 promotes synaptonemal complex assembly by downregulating PP2A-B56.

ABSTRACT: Meiosis creates genetic diversity by recombination and segregation of chromosomes. The synaptonemal complex assembles during meiotic prophase I and assists faithful exchanges between homologous chromosomes, but how its assembly/disassembly is regulated remains to be understood. Here, we report how two major posttranslational modifications, phosphorylation and ubiquitination, cooperate to promote synaptonemal complex assembly. We found that the ubiquitin ligase complex SCF is important for assembly and maintenance of the synaptonemal complex in Drosophila female meiosis. This function of SCF is mediated by two substrate-recognizing F-box proteins, Slmb/βTrcp and Fbxo42. SCF-Fbxo42 down-regulates the phosphatase subunit PP2A-B56, which is important for synaptonemal complex assembly and maintenance.

SUBMITTER: Barbosa P

PROVIDER: S-EPMC7780726 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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SCF-Fbxo42 promotes synaptonemal complex assembly by downregulating PP2A-B56.

Barbosa Pedro P Zhaunova Liudmila L Debilio Simona S Steccanella Verdiana V Kelly Van V Ly Tony T Ohkura Hiroyuki H

The Journal of cell biology 20210201 2

Meiosis creates genetic diversity by recombination and segregation of chromosomes. The synaptonemal complex assembles during meiotic prophase I and assists faithful exchanges between homologous chromosomes, but how its assembly/disassembly is regulated remains to be understood. Here, we report how two major posttranslational modifications, phosphorylation and ubiquitination, cooperate to promote synaptonemal complex assembly. We found that the ubiquitin ligase complex SCF is important for assemb ...[more]

PMID: 33382409

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SCF-Fbxo42 promotes synaptonemal complex assembly by downregulating PP2A-B56

Project description:Meiosis creates genetic diversity by recombination and segregation of chromosomes. The synaptonemal complex assembles during meiotic prophase I and assists faithful exchanges between homologous chromosomes, but how its assembly/disassembly is regulated remains to be understood. Here we report how two major post-translational modifications, phosphorylation and ubiquitination, co-operate to promote synaptonemal complex assembly. We found that the ubiquitin ligase complex SCF is important for assembly and maintenance of the synaptonemal complex in Drosophila female meiosis. This function of SCF is mediated by two substrate-recognising F-box proteins, Slmb/βTrcp and Fbxo42. SCF-Fbxo42 downregulates the phosphatase subunit PP2A-B56, which is important for synaptonemal complex assembly and maintenance.

2020-12-07 | PXD022755 | Pride

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