title: Meiotic telomere clustering requires actin for its formation and cohesin for its resolution.
abstract: In diploid organisms, meiosis reduces the chromosome number by half during the formation of haploid gametes. During meiotic prophase, telomeres transiently cluster at a limited sector of the nuclear envelope (bouquet stage) near the spindle pole body (SPB). Cohesin is a multisubunit complex that contributes to chromosome segregation in meiosis I and II divisions. In yeast meiosis, deficiency for Rec8 cohesin subunit induces telomere clustering to persist, whereas telomere cluster-SPB colocalization is defective. These defects are rescued by expressing the mitotic cohesin Scc1 in rec8delta meiosis, whereas bouquet-stage exit is independent of Cdc5 pololike kinase. An analysis of living Saccharomyces cerevisiae meiocytes revealed highly mobile telomeres from leptotene up to pachytene, with telomeres experiencing an actin- but not microtubule-dependent constraint of mobility during the bouquet stage. Our results suggest that cohesin is required for exit from actin polymerization-dependent telomere clustering and for linking the SPB to the telomere cluster in synaptic meiosis.
authors: Max-Planck-Institute for Molecular Genetics, D-14195 Berlin, Germany.
authors: Edgar
authors: E
authors: Trelles-Sticken
authors: Caroline
authors: C
authors: Adelfalk
authors: Josef
authors: J
authors: Loidl
authors: Harry
authors: H
authors: Scherthan
mesh_terms: D000199:Actins / Q000502:physiology*; D018797:Cell Cycle Proteins / Q000378:metabolism / Q000502:physiology*; D002467:Cell Nucleus / Q000235:genetics / Q000502:physiology; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism; D015825:Chromosomes, Fungal / Q000502:physiology; D005656:Fungal Proteins / Q000502:physiology*; D049452:Green Fluorescent Proteins / Q000235:genetics; D008540:Meiosis; D008870:Microtubules / Q000502:physiology; D009154:Mutation; D009685:Nuclear Envelope / Q000502:physiology; D009687:Nuclear Proteins / Q000502:physiology*; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000502:physiology* / Q000648:ultrastructure; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism; D000089804:Shelterin Complex; D008941:Spindle Apparatus; D016615:Telomere / Q000235:genetics / Q000502:physiology*; D034501:Telomere-Binding Proteins / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D000097722:Cohesins
chemical_list: D000199:Actins; D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D005656:Fungal Proteins; D049452:Green Fluorescent Proteins; D009687:Nuclear Proteins; D011494:Protein Kinases; D017346:Protein Serine-Threonine Kinases; D029701:Saccharomyces cerevisiae Proteins; D000089804:Shelterin Complex; D034501:Telomere-Binding Proteins; D014157:Transcription Factors; D000097722:Cohesins; C440829:RAP1 protein, S cerevisiae; C502898:REC8 protein, S cerevisiae; C081927:CDC5 protein, S cerevisiae