2xl2

Publication Abstract from PubMed

Histone modification is well established as a fundamental mechanism driving the regulation of transcription, replication and DNA repair through the control of chromatin structure. Likewise, it is apparent that incorrect targeting of histone modifications contributes to misregulated gene expression and hence to developmental disorders and diseases of genomic instability such as cancer. The KMT2 family of SET domain methyltransferases, typified by MLL1, are responsible for histone H3 lysine-4 methylation, a marker of active genes. To ensure that this modification is correctly targeted, a multi-protein complex associates with the methyltransferase and directs activity. We have identified a novel interaction site on the core complex protein WDR5, and mapped the complementary site on its partner RbBP5. We have characterised this interaction by X-ray crystallography and show how it is fundamental to the assembly of the complex and to the regulation of methyltransferase activity. We show which region of RbBP5 contributes directly to MLL activation and combine our structural and biochemical data to produce a model to show how WDR5 and RbBP5 act cooperatively to stimulate activity.

Characterisation of a novel WDR5 binding site that recruits RbBP5 through a conserved motif and enhances methylation of H3K4 by MLL1.,Odho Z, Southall SM, Wilson JR J Biol Chem. 2010 Aug 17. PMID:20716525^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.