Dynamic Phosphorylation of CENP-A at Ser68 Orchestrates Its Cell-Cycle-Dependent Deposition at Centromeres

The H3 histone variant CENP-A is an epigenetic marker critical for the centromere identity and function. However, the precise regulation of the spatiotemporal deposition and propagation of CENP-A at centromeres during the cell cycle is still poorly understood. Here, we show that CENP-A is phosphorylated at Ser68 during early mitosis by Cdk1. Our results demonstrate that phosphorylation of Ser68 eliminates the binding of CENP-A to the assembly factor HJURP, thus preventing the premature loading of CENP-A to the centromere prior to mitotic exit. Because Cdk1 activity is at its minimum at the mitotic exit, the ratio of Cdk1/PP1α activity changes in favor of Ser68 dephosphorylation, thus making CENP-A available for centromeric deposition by HJURP. Thus, we reveal that dynamic phosphorylation of CENP-A Ser68 orchestrates the spatiotemporal assembly of newly synthesized CENP-A at active centromeres during the cell cycle. [Display omitted] •Ser68 is critical for the in vivo function of CENP-A•Ser68 phosphorylation prevents binding of CENP-A to HJURP•Cdk1 and PP1α control the phosphorylation status of CENP-A Ser68•Ser68 phosphorylation orchestrates the spatiotemporal deposition of CENP-A CENP-A Ser68 is a critical regulatory site for CENP-A recognition of its chaperone, HJURP. The dynamic phosphoregulation of Ser68 is controlled by Cdk1/PP1α, allowing cell-cycle-dependent orchestration of centromeric CENP-A deposition.