Phosphorylation of HsMis13 by Aurora B kinase is essential for assembly of functional kinetochore.
Chromosome movements in mitosis are orchestrated by dynamic interactions between spindle microtubules and the kinetochore, a multiprotein complex assembled onto centromeric DNA of the chromosome. Here we show that phosphorylation of human HsMis13 by Aurora B kinase is required for functional kinetochore assembly in HeLa cells. Aurora B interacts with HsMis13 in vitro and in vivo. HsMis13 is a cognate substrate of Aurora B, and the phosphorylation sites were mapped to Ser-100 and Ser-109. Suppression of Aurora B kinase by either small interfering RNA or chemical inhibitors abrogates the localization of HsMis13 but not HsMis12 to the kinetochore. In addition, non-phosphorylatable but not wild type and phospho-mimicking HsMis13 failed to localize to the kinetochore, demonstrating the requirement of phosphorylation by Aurora B for the assembly of HsMis13 to kinetochore. In fact, localization of HsMis13 to the kinetochore is spatiotemporally regulated by Aurora B kinase, which is essential for recruiting outer kinetochore components such as Ndc80 components and CENP-E for functional kinetochore assembly. Importantly, phospho-mimicking mutant HsMis13 restores the assembly of CENP-E to the kinetochore, and tension developed across the sister kinetochores in Aurora B-inhibited cells. Thus, we reason that HsMis13 phosphorylation by Aurora B is required for organizing a stable bi-oriented microtubule kinetochore attachment that is essential for faithful chromosome segregation in mitosis.
Yang
Yong
Y
Hefei National Laboratory for Physical Sciences at Micro-scale and University of Science and Technology of China, Hefei 230027, China.
Wu
Fang
F
Ward
Tarsha
T
Yan
Feng
F
Wu
Quan
Q
Wang
Zhaoyang
Z
McGlothen
Tanisha
T
Peng
Wei
W
You
Tianpa
T
Sun
Mingkuan
M
Cui
Taixing
T
Hu
Renming
R
Dou
Zhen
Z
Zhu
Jingde
J
Xie
Wei
W
Rao
Zihe
Z
Ding
Xia
X
Yao
Xuebiao
X
D064107:Aurora Kinase B; D064127:Aurora Kinases; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism*; D020090:Chromosome Segregation / Q000502:physiology*; D002877:Chromosomes, Human / Q000235:genetics / Q000378:metabolism*; D003598:Cytoskeletal Proteins; D006367:HeLa Cells; D006801:Humans; D018386:Kinetochores / Q000378:metabolism*; D008870:Microtubules / Q000235:genetics / Q000378:metabolism; D008938:Mitosis / Q000502:physiology*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics
D002868:Chromosomal Proteins, Non-Histone; D003598:Cytoskeletal Proteins; C532764:DSN1 protein, human; C120529:NDC80 protein, human; D009687:Nuclear Proteins; D047428:Protein Kinase Inhibitors; D034741:RNA, Small Interfering; C068688:centromere protein E; C576921:AURKB protein, human; D064107:Aurora Kinase B; D064127:Aurora Kinases; D017346:Protein Serine-Threonine Kinases