Global Control of Histone Modification by the Anaphase-Promoting Complex

Abstract

Acetylation and phosphorylation of the amino-terminal tails of the core histones fluctuate on a global scale in concert with other major events in chromosome metabolism. A ubiquitin ligase, the anaphase-promoting complex (APC), controls events in chromosome metabolism such as sister chromatid cohesion and may regulate H3 phosphorylation by targeting Aurora A, one of several S10-directed H3 kinases in vertebrate cells, for destruction by the proteasome. Our analysis of apc10Δ and apc11^ts loss-of-function mutants reveals that the APC controls the global level of H3 S10 phosphorylation in cycling yeast cells. Surprisingly, it also regulates dephosphorylation of H3 and global deacetylation of H2B, H3, and H4 during exit from the cell cycle into G₀. Genetic, biochemical, and microarray analyses suggest that APC-dependent cell cycle control of H3 phosphorylation is exerted at the level of an Aurora H3 kinase, Ipl1p, while APC-dependent transcriptional induction of GLC7, an essential H3 phosphatase, contributes to sustained H3 dephosphorylation upon cell cycle withdrawal. Collectively, our results establish that core histone acetylation state and H3 phosphorylation are physiologically regulated by the APC and suggest a model in which global reconfiguration of H3 phosphorylation state involves APC-dependent control of both an H3 kinase and a conserved phosphatase.

ACKNOWLEDGMENTS

V. Ramaswamy and J. S. Williams contributed equally to this work.

We are grateful to M. Grunstein and A. Carmen for expression plasmids and advice on the generation and use of antihistone antisera. A. Page, J. Leverson, T. Hunter, H. Steiner, M. Ellison, K. Tatchell, D. Wolf, C. Chan, and J. Stone kindly made available various yeast reagents. We thank T. Harkness, D. Hockman, A. Ghavidel, J. Yang, J. Cooper, and R. Moudgil for technical advice and assistance.

This work was supported by grants to M.C.S. from the Canadian Institutes for Health Research and the Alberta Heritage Foundation for Medical Research. V.R. and R.S. were supported by summer studentships from the AHFMR.