title: Cohesin is needed for bipolar mitosis in human cells.
abstract: Multi-polar mitosis is strongly linked with aggressive cancers and it is a histological diagnostic of tumor-grade. However, factors that cause chromosomes to segregate to more than two spindle poles are not well understood. Here we show that cohesins Rad21, Smc1 and Smc3 are required for bipolar mitosis in human cells. After Rad21 depletion, chromosomes align at the metaphase plate and bipolar spindles assemble in most cases, but in anaphase the separated chromatids segregate to multiple poles. Time-lapse microscopy revealed that the spindle poles often become split in Rad21-depleted metaphase cells. Interestingly, exogenous expression of non-cleavable Rad21 results in multi-polar anaphase. Since cohesins are present at the spindle poles in mitosis, these data are consistent with a non-chromosomal function of cohesin.
authors.affiliation: Department of Genetics, Cell Biology & Development, University of Minnesota Medical School, Minneapolis, MN, USA.
authors.forename: Laura A
authors.initials: LA
authors.lastname: Díaz-Martínez
authors.forename: Nicole A
authors.initials: NA
authors.lastname: Beauchene
authors.forename: Katherine
authors.initials: K
authors.lastname: Furniss
authors.forename: Pedro
authors.initials: P
authors.lastname: Esponda
authors.forename: Juan F
authors.initials: JF
authors.lastname: Giménez-Abián
authors.forename: Duncan J
authors.initials: DJ
authors.lastname: Clarke
mesh_terms: D000705:Anaphase; D018797:Cell Cycle Proteins / Q000378:metabolism*; D002502:Centrioles / Q000378:metabolism; D011508:Chondroitin Sulfate Proteoglycans / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism*; D020090:Chromosome Segregation; D004268:DNA-Binding Proteins; D006367:HeLa Cells; D006801:Humans; D008677:Metaphase; D008938:Mitosis; D009687:Nuclear Proteins / Q000378:metabolism; D010750:Phosphoproteins / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D000097722:Cohesins; D000098550:Structural Maintenance of Chromosome Protein 1
chemical_list: D018797:Cell Cycle Proteins; D011508:Chondroitin Sulfate Proteoglycans; D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins; D034741:RNA, Small Interfering; D000097722:Cohesins; D000098550:Structural Maintenance of Chromosome Protein 1; C429022:RAD21 protein, human; C492318:SMC3 protein, human