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Molli PR , Li DQ , Bagheri-Yarmand R , Pakala SB , Katayama H , Sen S , Iyer J , Chernoff J , Tsai MY , Nair SS , Kumar R
Arpc1b, a centrosomal protein, is both an activator and substrate of Aurora A
Journal of Cell Biology. 2010 Jul;190(1) :101-114
PMCID: PMCID: PMC2911675   
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Abstract
Here we provide evidence in support of an inherent role for Arpc1b, a component of the Arp2/3 complex, in regulation of mitosis and demonstrate that its depletion inhibits Aurora A activation at the centrosome and impairs the ability of mammalian cells to enter mitosis. We discovered that Arpc1b colocalizes with gamma-tubulin at centrosomes and stimulates Aurora A activity. Aurora A phosphorylates Arpc1b on threonine 21, and expression of Arpc1b but not a nonphosphorylatable Arpc1b mutant in mammalian cells leads to Aurora A kinase activation and abnormal centrosome amplification in a Pak1-independent manner. Together, these findings reveal a new function for Arpc1b in centrosomal homeostasis. Arpc1b is both a physiological activator and substrate of Aurora A kinase and these interactions help to maintain mitotic integrity in mammalian cells.
Notes
Molli, Poonam R. Li, Da-Qiang Bagheri-Yarmand, Rozita Pakala, Suresh B. Katayama, Hiroshi Sen, Subrata Iyer, Jyoti Chernoff, Jonathan Tsai, Ming-Ying Nair, Sujit S. Kumar, Rakesh Rockefeller univ press New york 624cc