HJURP is a cell-cycle-dependent maintenance and deposition factor of CENP-A at centromeres.

Dunleavy, Elaine M; Roche, Danièle; Tagami, Hideaki; Lacoste, Nicolas; Ray-Gallet, Dominique; Nakamura, Yusuke; Daigo, Yataro; Nakatani, Yoshihiro et al. · Cell · 2009

basic_science · Level V

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Abstract

The histone H3 variant CenH3, called CENP-A in humans, is central in centromeric chromatin to ensure proper chromosome segregation. In the absence of an underlying DNA sequence, it is still unclear how CENP-A deposition at centromeres is determined. Here, we purified non-nucleosomal CENP-A complexes to identify direct CENP-A partners involved in such a mechanism and identified HJURP. HJURP was not detected in H3.1- or H3.3-containing complexes, indicating its specificity for CENP-A. HJURP centromeric localization is cell cycle regulated, and its transient appearance at the centromere coincides precisely with the proposed time window for new CENP-A deposition. Furthermore, HJURP downregulation leads to a major reduction in CENP-A at centromeres and impairs deposition of newly synthesized CENP-A, causing mitotic defects. We conclude that HJURP is a key factor for CENP-A deposition and maintenance at centromeres.

Medical subject headings