title: Interaction of Sororin protein with polo-like kinase 1 mediates resolution of chromosomal arm cohesion.
abstract: Unlike in budding yeast, sister chromatid cohesion in vertebrate cells is resolved in two steps: cohesin complexes are removed from sister chromatid arms during prophase via phosphorylation, whereas centromeric cohesins are removed at anaphase by Separase. Phosphorylation of cohesin subunit SA2 by polo-like kinase 1 (Plk1) is required for the removal of cohesins at prophase, but how Plk1 is recruited to phosphorylate SA2 during prophase is currently not known. Here we report that Sororin, a cohesin-interacting protein essential for sister chromatid cohesion, plays a novel role in the resolution of sister chromatid arms by direct interaction with Plk1. We identified an evolutionarily conserved motif (ST(159)P) on Sororin, which was phosphorylated by Cdk1/cyclin B and bound to the polo box domain of Plk1. Mutating Thr(159) into alanine prevented the interaction of Plk1 and Sororin and inhibited the resolution of chromosomal arm cohesion. We propose that Sororin is phosphorylated by Cdk1/cyclin B at prophase and acts as a docking protein to bring Plk1 into proximity with SA2, resulting in the phosphorylation of SA2 and the removal of cohesin complexes from chromosomal arms.
authors: Texas Children's Cancer and Hematology Center, Department of Pediatric Hematology/Oncology, Baylor College of Medicine, Houston, Texas 77030. Electronic address: nzhang@bcm.edu.
authors: Nenggang
authors: N
authors: Zhang
authors: Texas Children's Cancer and Hematology Center, Department of Pediatric Hematology/Oncology, Baylor College of Medicine, Houston, Texas 77030.
authors: Anil K
authors: AK
authors: Panigrahi
authors: Texas Children's Cancer and Hematology Center, Department of Pediatric Hematology/Oncology, Baylor College of Medicine, Houston, Texas 77030.
authors: Qilong
authors: Q
authors: Mao
authors: Texas Children's Cancer and Hematology Center, Department of Pediatric Hematology/Oncology, Baylor College of Medicine, Houston, Texas 77030. Electronic address: pati@bcm.edu.
authors: Debananda
authors: D
authors: Pati
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D020816:Amino Acid Motifs; D019943:Amino Acid Substitution; D016203:CDC2 Protein Kinase / Q000235:genetics / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002842:Chromatids; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism*; D019926:Cyclin B / Q000235:genetics / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D020125:Mutation, Missense; D010766:Phosphorylation / Q000502:physiology; D011418:Prophase / Q000502:physiology; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D000097722:Cohesins; D000097869:Polo-Like Kinase 1
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D016203:CDC2 Protein Kinase; D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D019926:Cyclin B; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D000097722:Cohesins; D000097869:Polo-Like Kinase 1; C500695:CDCA5 protein, human