14-3-3 Interaction with Histone H3 Involves a Dual Modification Pattern of Phosphoacetylation

Abstract

Histone modifications occur in precise patterns and are proposed to signal the recruitment of effector molecules that profoundly impact chromatin structure, gene regulation, and cell cycle events. The linked modifications serine 10 phosphorylation and lysine 14 acetylation on histone H3 (H3S10phK14ac), modifications conserved from Saccharomyces cerevisiae to humans, are crucial for transcriptional activation of many genes. However, the mechanism of H3S10phK14ac involvement in these processes is unclear. To shed light on the role of this dual modification, we utilized H3 peptide affinity assays to identify H3S10phK14ac-interacting proteins. We found that the interaction of the known phospho-binding 14-3-3 proteins with H3 is dependent on the presence of both of these marks, not just phosphorylation alone. This is true of mammalian 14-3-3 proteins as well as the yeast homologues Bmh1 and Bmh2. The importance of acetylation in this interaction is also seen in vivo, where K14 acetylation is required for optimal Bmh1 recruitment to the GAL1 promoter during transcriptional activation.

ACKNOWLEDGMENTS

The anti-Bmh1 antibody was a kind gift from G. P. H. van Heusden. We thank Viji Shridhar for help with cloning of Bmh1 and Bmh2, Kristin Ingvarsdottir for the FLAG-H3 strain, David Bungard for the FLAG-H3K14R strain, J. Govin for help in preparing figures, and W. Alston for help in preparing the text for publications.

An NRSA Training Program in Basic Cancer Research training grant (5T32 CA09171-28) and an American Cancer Society postdoctoral fellowship made possible by the Aramark Corporation supported the work of W.W. Research was supported by grants from NIH (GM55360) and NSF (MCB-9604208) to S.L.B.