Analysis of p300/CBP Histone Acetyltransferase Regulation Using Circular Permutation and Semisynthesis

Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, USA.
Journal of the American Chemical Society (Impact Factor: 12.11). 02/2010; 132(4):1222-3. DOI: 10.1021/ja909466d
Source: PubMed


The histone acetyltransferase (HAT) p300/CBP has been shown to undergo autoacetylation on lysines in an apparent regulatory loop that stimulates HAT activity. Here we have developed a strategy to introduce acetyl-Lys at up to six known modification sites in p300/CBP HAT using a combination of circular permutation and expressed protein ligation. We show that these semisynthetic, circularly permuted acetylated proteins retain high affinity for an acetyl-CoA substrate analogue and that HAT activity correlates positively with degree of acetylation. This study provides novel evidence for control of p300/CBP HAT activity by site-specific autoacetylation and outlines a potentially general strategy for using expressed protein ligation and circular permutation to chemically interrogate internal regions of proteins.

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