English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We have studied four Caenorhabditis elegans homologs of the Rad21/Scc1/Rec8 sister-chromatid cohesion protein family. Based on the RNAi phenotype and protein localization, it is concluded that one of them, W02A2.6p, is the likely worm ortholog of yeast Rec8p. The depletion of C. elegans W02A2.6p (called REC-8) by RNAi, induced univalent formation and splitting of chromosomes into sister chromatids at diakinesis. Chromosome synapsis at pachytene was defective, but primary homology recognition seemed unaffected, as a closer-than-random association of homologous fluorescence in situ hybridization (FISH) signals at leptotene/zygotene was observed. Depletion of REC-8 also induced chromosome fragmentation at diakinesis. We interpret these fragments as products of unrepaired meiotic double-stranded DNA breaks (DSBs), because fragmentation was suppressed in a spo-11 background. Thus, REC-8 seems to be required for successful repair of DSBs. The occurrence of DSBs in REC-8-depleted meiocytes suggests that DSB formation does not depend on homologous synapsis. Anti-REC-8 immunostaining decorated synaptonemal complexes (SCs) at pachytene and chromosomal axes in bivalents and univalents at diakinesis. Between metaphase I and metaphase II, REC-8 is partially lost from the chromosomes. The partial loss of REC-8 from chromosomes between metaphase I and metaphase II suggests that worm REC-8 might function similarly to yeast Rec8p. The loss of yeast Rec8p from chromosome arms at meiosis I and centromeres at meiosis II coordinates the disjunction of homologs and sister chromatids at the two meiotic divisions.

A Caenorhabditis elegans cohesion protein with functions in meiotic chromosome pairing and disjunction