Cohesin subunit SMC1 associates with mitotic microtubules at the spindle pole.
Accurate mitotic chromosome segregation depends on the formation of a microtubule-based bipolar spindle apparatus. We report that the cohesin subunit structural maintenance of chromosomes subunit 1 (SMC1) is recruited to microtubule-bound RNA export factor 1 (Rae1) at the mitotic spindle pole. We locate the Rae1-binding site to a 21-residue-long region, SMC1(947-967) and provide several lines of evidence that phosphorylation of Ser(957) and Ser(966) of SMC1 stimulates binding to Rae1. Imbalances in these assembly pathways caused formation of multipolar spindles. Our data suggest that cohesin's known bundling function for chromatids in mitotic and interphase cells extends to microtubules at the spindle pole.
Wong
Richard W
RW
Laboratory of Cell Biology, Howard Hughes Medical Institute, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA. rwong@staff.kanazawa-u.ac.jp
Blobel
Günter
G
D034961:Antigens, Nuclear / Q000378:metabolism; D064007:Ataxia Telangiectasia Mutated Proteins; D001665:Binding Sites; D018797:Cell Cycle Proteins / Q000032:analysis / Q000378:metabolism*; D002868:Chromosomal Proteins, Non-Histone / Q000032:analysis / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000032:analysis / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D006367:HeLa Cells; D006801:Humans; D008870:Microtubules / Q000378:metabolism*; D034521:Nuclear Matrix-Associated Proteins / Q000032:analysis / Q000378:metabolism; D029543:Nucleocytoplasmic Transport Proteins / Q000032:analysis / Q000378:metabolism; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000032:analysis / Q000378:metabolism; D008941:Spindle Apparatus / Q000378:metabolism* / Q000648:ultrastructure; D014162:Transfection; D025521:Tumor Suppressor Proteins / Q000032:analysis / Q000378:metabolism; D000098550:Structural Maintenance of Chromosome Protein 1
D034961:Antigens, Nuclear; D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; C050045:NUMA1 protein, human; D034521:Nuclear Matrix-Associated Proteins; D029543:Nucleocytoplasmic Transport Proteins; C490522:RAE1 protein, human; D025521:Tumor Suppressor Proteins; D000098550:Structural Maintenance of Chromosome Protein 1; C576324:ATM protein, human; D064007:Ataxia Telangiectasia Mutated Proteins; D017346:Protein Serine-Threonine Kinases