Cohesin is needed for bipolar mitosis in human cells.
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.
Díaz-Martínez
Laura A
LA
Department of Genetics, Cell Biology & Development, University of Minnesota Medical School, Minneapolis, MN, USA.
Beauchene
Nicole A
NA
Furniss
Katherine
K
Esponda
Pedro
P
Giménez-Abián
Juan F
JF
Clarke
Duncan J
DJ
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
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