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CENP-H, a constitutive centromere component, is required for centromere targeting of CENP-C in vertebrate cells.

ABSTRACT: CENP-H has recently been discovered as a constitutive component of the centromere that co-localizes with CENP-A and CENP-C throughout the cell cycle. The precise function, however, remains poorly understood. We examined the role of CENP-H in centromere function and assembly by generating a conditional loss-of-function mutant in the chicken DT40 cell line. In the absence of CENP-H, cell cycle arrest at metaphase, consistent with loss of centromere function, was observed. Immunocytochemical analysis of the CENP-H-deficient cells demonstrated that CENP-H is necessary for CENP-C, but not CENP-A, localization to the centromere. These findings indicate that centromere assembly in vertebrate cells proceeds in a hierarchical manner in which localization of the centromere-specific histone CENP-A is an early event that occurs independently of CENP-C and CENP-H.

SUBMITTER: Fukagawa T

PROVIDER: S-EPMC125570 | biostudies-literature | 2001 Aug

REPOSITORIES: biostudies-literature

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CENP-H, a constitutive centromere component, is required for centromere targeting of CENP-C in vertebrate cells.

Fukagawa T T Mikami Y Y Nishihashi A A Regnier V V Haraguchi T T Hiraoka Y Y Sugata N N Todokoro K K Brown W W Ikemura T T

The EMBO journal 20010801 16

CENP-H has recently been discovered as a constitutive component of the centromere that co-localizes with CENP-A and CENP-C throughout the cell cycle. The precise function, however, remains poorly understood. We examined the role of CENP-H in centromere function and assembly by generating a conditional loss-of-function mutant in the chicken DT40 cell line. In the absence of CENP-H, cell cycle arrest at metaphase, consistent with loss of centromere function, was observed. Immunocytochemical analys ...[more]

PMID: 11500386

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