Nek2A kinase regulates the localization of numatrin to centrosome in mitosis.
Chromosome segregation in mitosis is orchestrated by the kinetochore and spindle microtubules stemming from two centrosomes. Our recent studies demonstrated the importance of Nek2A in faithful chromosome segregation during mitosis. Here, we report that Nek2A regulates the function of numatrin in mitosis. The biochemical interaction between Nek2A and numatrin in mitotic cells was revealed by a set of reciprocal immunoprecipitation experiments using Nek2A and numatrin antibodies, respectively. The interaction is validated by a pull-down assay using recombinant Nek2A and numatrin proteins. Moreover, our immunofluorescence studies demonstrate that numatrin becomes centrosome-associated as the cell enters into mitosis and depart from the centrosome after sister chromatid separation in anaphase. The co-localization of numatrin and Nek2A to the centrosome suggests their interaction with and involvement in centrosome function. Indeed, elimination of Nek2A kinase by siRNA diminished its association with the centrosome. Furthermore, we show that numatrin is phosphorylated by wild type but not kinase-death Nek2A. Our studies suggest that the Nek2A kinase cascade is essential for the localization of numatrin to the centrosome.
Yao
Jianhui
J
School of Life Sciences, University of Science and Technology of China, Hefei 230027, PR China.
Fu
Chuanhai
C
Ding
Xia
X
Guo
Zhen
Z
Zenreski
Arzhang
A
Chen
Yong
Y
Ahmed
Kashif
K
Liao
Jian
J
Dou
Zhen
Z
Yao
Xuebiao
X
D018385:Centrosome / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D007150:Immunohistochemistry; D008938:Mitosis / Q000502:physiology*; D000072379:NIMA-Related Kinases; D009687:Nuclear Proteins / Q000378:metabolism*; D000090243:Nucleophosmin; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism
C000716967:NPM1 protein, human; D009687:Nuclear Proteins; D034741:RNA, Small Interfering; D011993:Recombinant Fusion Proteins; D000090243:Nucleophosmin; C089441:NEK2 protein, human; D000072379:NIMA-Related Kinases; D017346:Protein Serine-Threonine Kinases