A chemical method for labeling lysine methyltransferase substrates.

Published

Journal Article

Several protein lysine methyltransferases (PKMTs) modify histones to regulate chromatin-dependent cellular processes, such as transcription, DNA replication and DNA damage repair. PKMTs are likely to have many additional substrates in addition to histones, but relatively few nonhistone substrates have been characterized, and the substrate specificity for many PKMTs has yet to be defined. Thus, new unbiased methods are needed to find PKMT substrates. Here, we describe a chemical biology approach for unbiased, proteome-wide identification of novel PKMT substrates. Our strategy makes use of an alkyne-bearing S-adenosylmethionine (SAM) analogue, which is accepted by the PKMT, SETDB1, as a cofactor, resulting in the enzymatic attachment of a terminal alkyne to its substrate. Such labeled proteins can then be treated with azide-functionalized probes to ligate affinity handles or fluorophores to the PKMT substrates. As a proof-of-concept, we have used SETDB1 to transfer the alkyne moiety from the SAM analogue onto a recombinant histone H3 substrate. We anticipate that this chemical method will find broad use in epigenetics to enable unbiased searches for new PKMT substrates by using recombinant enzymes and unnatural SAM cofactors to label and purify many substrates simultaneously from complex organelle or cell extracts.

Full Text

Duke Authors

Cited Authors

  • Binda, O; Boyce, M; Rush, JS; Palaniappan, KK; Bertozzi, CR; Gozani, O

Published Date

  • January 24, 2011

Published In

Volume / Issue

  • 12 / 2

Start / End Page

  • 330 - 334

PubMed ID

  • 21243721

Pubmed Central ID

  • 21243721

Electronic International Standard Serial Number (EISSN)

  • 1439-7633

Digital Object Identifier (DOI)

  • 10.1002/cbic.201000433

Language

  • eng

Conference Location

  • Germany