Csm4, in collaboration with Ndj1, mediates telomere-led chromosome dynamics and recombination during yeast meiosis.

Csm4, in collaboration with Ndj1, mediates telomere-led chromosome dynamics and recombination during yeast meiosis.

Blog Article

Chromosome movements are a general feature of mid-prophase of meiosis.In budding yeast, meiotic chromosomes exhibit dynamic hacklinkci.com movements, led by nuclear envelope (NE)-associated telomeres, throughout the zygotene and pachytene stages.Zygotene motion underlies the global tendency for colocalization of NE-associated chromosome ends in a "bouquet." In this study, we identify Csm4 as a new molecular participant in these processes and show that, unlike the two previously identified components, Ndj1 and Mps3, Csm4 is not required for meiosis-specific telomere/NE association.

Instead, it acts to couple telomere/NE ensembles to a force generation mechanism.Mutants lacking Csm4 and/or Ndj1 display the following closely related phenotypes: (i) elevated crossover (CO) frequencies and decreased CO interference without abrogation of normal pathways; (ii) delayed progression of recombination, and recombination-coupled chromosome morphogenesis, with resulting delays in the MI division; and (iii) nondisjunction of homologs at the MI division for some reason other than absence of (the obligatory) CO(s).The recombination effects are discussed in the context of a model where the underlying defect is chromosome movement, cocktail tree for sale the absence of which results in persistence of inappropriate chromosome relationships that, in turn, results in the observed mutant phenotypes.