PMID: 27501476

Authors:

Gai W, Li H, Jiang H, Long Y, Liu D

Title:

Crystal structures of SIRT3 reveal that the alpha2-alpha3 loop and alpha3-helix affect the interaction with long-chain acyl lysine.

Journal:

FEBS Lett. 2016 Sep;590(17):3019-28. doi: 10.1002/1873-3468.12345. Epub 2016 Aug , 24.

Abstract:

SIRT1-7 play important roles in many biological processes and age-related diseases. In addition to a NAD(+) -dependent deacetylase activity, they can catalyze several other reactions, including the hydrolysis of long-chain fatty acyl lysine. To study the binding modes of sirtuins to long-chain acyl lysines, we solved the crystal structures of SIRT3 bound to either a H3K9-myristoylated- or a H3K9-palmitoylated peptide. Interaction of SIRT3 with the palmitoyl group led to unfolding of the alpha3-helix. The myristoyl and palmitoyl groups bind to the C-pocket and an allosteric site near the alpha3-helix, respectively. We found that the residues preceding the alpha3-helix determine the size of the C-pocket. The flexibility of the alpha2-alpha3 loop and the plasticity of the alpha3-helix affect the interaction with long-chain acyl lysine.