Cellular functions of MLL/SET-family histone H3 lysine 4 methyltransferase components

Abstract

The MLL/SET family of histone H3 lysine 4 methyltransferases form enzyme complexes with core subunits ASH2L, WDR5, RbBP5, and DPY-30 (often abbreviated WRAD), and are responsible for global histone H3 lysine 4 methylation, a hallmark of actively transcribed chromatin in mammalian cells. Accordingly, the function of these proteins is required for a wide variety of processes including stem cell differentiation, cell growth and division, body segmentation, and hematopoiesis. While most work on MLL-WRAD has focused on the function this core complex in histone methylation, recent studies indicate that MLL-WRAD proteins interact with a variety of other proteins and lncRNAs and can localize to cellular organelles beyond the nucleus. In this review, we focus on the recently described activities and interacting partners of MLL-WRAD both inside and outside the nucleus.

Keywords

H3K4MT / histone H3 lysine 4 methyltransferase / WDR5 / RbBP5 / ASH2L / DPY-30 / SET / MLL / WRAD / Oct4 / MYC / cell biology / protein lysine methylation

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Compliance with ethics guidelines

Jeffrey Bailey and Dzwokai Ma declare that they have no conflicts of interest. This manuscript is a review article and does not involve a research protocol requiring approval by the relevant institutional review board or ethics committee.

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg