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Functional redundancy of paralogs of an anaphase promoting complex/cyclosome subunit in Caenorhabditis elegans meiosis.

Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
Genetics (Impact Factor: 4.87). 10/2010; 186(4):1285-93. DOI: 10.1534/genetics.110.123463
Source: PubMed

ABSTRACT The anaphase promoting complex/cyclosome (APC/C) mediates the metaphase-to-anaphase transition by instructing the ubiquitination and turnover of key proteins at this stage of the cell cycle. We have recovered a gain-of-function allele in an APC5 subunit of the anaphase promoting complex/cyclosome. This finding led us to investigate further the role of APC5 in Caenorhabditis elegans, which contains two APC5 paralogs. We have shown that these two paralogs, such-1 and gfi-3, are coexpressed in the germline but have nonoverlapping expression patterns in other tissues. Depletion of such-1 or gfi-3 alone does not have a notable effect on the meiotic divisions; however, codepletion of these two factors results in meiotic arrest. In sum, the two C. elegans APC5 paralogs have a redundant function during the meiotic divisions.

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Available from: Benjamin D Ross, Aug 28, 2015
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    • "Identical meiotic arrest phenotypes have been generated through RNAi mediated depletion of any of the following: (a) any 1 of 11 different APC/C subunits (Davis et al. 2002; Dong et al. 2007; Kops et al. 2010; Green et al. 2011), (b) the CDC20 ortholog, fzy-1, or (c) any one of several proteasome subunits or the two ubiquitin genes, ubq-1 and ubq-2 (Sonnichsen et al. 2005). To date, the less severe RNAi depletion phenotypes of the Apc10-like subunits remain poorly characterized, and those of the two Apc5-like subunits (SUCH-1 and GFI-3) suggest that they function redundantly during meiosis (Stein et al. 2010). Yet despite the many new insights that these various biochemical, genetic, and structural studies are revealing in regard to the mechanistic details of the APC/C, both the composition and regulation of the APC/C remain incompletely understood, particularly as APC/C studies are extended into additional species and cell types. "
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    Genetics 07/2011; 189(2):549-60. DOI:10.1534/genetics.111.131714 · 4.87 Impact Factor
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    • "However, subjecting such-1 mutant animals simultaneously to gfi-3(RNAi) and such-1(RNAi) results in the vast majority of embryos being arrested in meiosis I (Stein et al. 2010, accompanying article in this issue), indicating that the two APC5 components act largely redundantly at this stage. Therefore, in contrast to the situation in Drosophila, where some APC/C substrates are turned over in embryos harboring a genetic null mutation in the sole APC5 gene ida (Bentley et al. 2002), the available evidence indicates that in C. elegans APC5 is essential for canonical APC/C function. "
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