4b5o

Publication Abstract from PubMed

Acetylation of lysine residues is an important posttranslational modification found in all domains of life. alpha-tubulin is specifically acetylated on lysine 40, a modification that serves to stabilize microtubules of axons and cilia. Whereas histone acetyltransferases have been extensively studied, there is no structural and mechanistic information available on alpha-tubulin acetyltransferases. Here, we present the structure of the human alpha-tubulin acetyltransferase catalytic domain bound to its cosubstrate acetyl-CoA at 1.05 A resolution. Compared with other lysine acetyltransferases of known structure, alpha-tubulin acetyltransferase displays a relatively well-conserved cosubstrate binding pocket but is unique in its active site and putative alpha-tubulin binding site. Using acetylation assays with structure-guided mutants, we map residues important for acetyl-CoA binding, substrate binding, and catalysis. This analysis reveals a basic patch implicated in substrate binding and a conserved glutamine residue required for catalysis, demonstrating that the family of alpha-tubulin acetyltransferases uses a reaction mechanism different from other lysine acetyltransferases characterized to date.

Atomic resolution structure of human alpha-tubulin acetyltransferase bound to acetyl-CoA.,Taschner M, Vetter M, Lorentzen E Proc Natl Acad Sci U S A. 2012 Nov 27;109(48):19649-54. doi:, 10.1073/pnas.1209343109. Epub 2012 Oct 15. PMID:23071318^[2]

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