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Sgt1 dimerization is negatively regulated by protein kinase CK2-mediated phosphorylation at Ser361.

ABSTRACT: The kinetochore, which consists of centromere DNA and structural proteins, is essential for proper chromosome segregation in eukaryotes. In budding yeast, Sgt1 and Hsp90 are required for the binding of Skp1 to Ctf13 (a component of the core kinetochore complex CBF3) and therefore for the assembly of CBF3. We have previously shown that Sgt1 dimerization is important for this kinetochore assembly mechanism. In this study, we report that protein kinase CK2 phosphorylates Ser(361) on Sgt1, and this phosphorylation inhibits Sgt1 dimerization.

SUBMITTER: Bansal PK

PROVIDER: S-EPMC2707205 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature

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Sgt1 dimerization is negatively regulated by protein kinase CK2-mediated phosphorylation at Ser361.

Bansal Parmil K PK Mishra Ashutosh A High Anthony A AA Abdulle Rashid R Kitagawa Katsumi K

The Journal of biological chemistry 20090427 28

The kinetochore, which consists of centromere DNA and structural proteins, is essential for proper chromosome segregation in eukaryotes. In budding yeast, Sgt1 and Hsp90 are required for the binding of Skp1 to Ctf13 (a component of the core kinetochore complex CBF3) and therefore for the assembly of CBF3. We have previously shown that Sgt1 dimerization is important for this kinetochore assembly mechanism. In this study, we report that protein kinase CK2 phosphorylates Ser(361) on Sgt1, and this ...[more]

PMID: 19398558

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