Mechanism of human SIRT1 activation by resveratrol. J Biol Chem 2005 Apr 29;280(17):17187-95
Date
03/08/2005Pubmed ID
15749705DOI
10.1074/jbc.M501250200Scopus ID
2-s2.0-20444444649 (requires institutional sign-in at Scopus site) 928 CitationsAbstract
The NAD+-dependent protein deacetylase family, Sir2 (or sirtuins), is important for many cellular processes including gene silencing, regulation of p53, fatty acid metabolism, cell cycle regulation, and life span extension. Resveratrol, a polyphenol found in wines and thought to harbor major health benefits, was reported to be an activator of Sir2 enzymes in vivo and in vitro. In addition, resveratrol was shown to increase life span in three model organisms through a Sir2-dependent pathway. Here, we investigated the molecular basis for Sir2 activation by resveratrol. Among the three enzymes tested (yeast Sir2, human SIRT1, and human SIRT2), only SIRT1 exhibited significant enzyme activation ( approximately 8-fold) using the commercially available Fluor de Lys kit (BioMol). To examine the requirements for resveratrol activation of SIRT1, we synthesized three p53 acetylpeptide substrates either lacking a fluorophore or containing a 7-amino-4-methylcoumarin (p53-AMC) or rhodamine 110 (p53-R110). Although SIRT1 activation was independent of the acetylpeptide sequence, resveratrol activation was completely dependent on the presence of a covalently attached fluorophore. Substrate competition studies indicated that the fluorophore decreased the binding affinity of the peptide, and, in the presence of resveratrol, fluorophore-containing substrates bound more tightly to SIRT1. Using available crystal structures, a model of SIRT1 bound to p53-AMC peptide was constructed. Without resveratrol, the coumarin of p53-AMC peptide is solvent-exposed and makes no significant contacts with SIRT1. We propose that binding of resveratrol to SIRT1 promotes a conformational change that better accommodates the attached coumarin group.
Author List
Borra MT, Smith BC, Denu JMAuthor
Brian C. Smith PhD Associate Professor in the Biochemistry department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AntioxidantsBinding Sites
Binding, Competitive
Cell Cycle
Chromatography, High Pressure Liquid
Coloring Agents
Coumarins
Crystallography, X-Ray
Gene Silencing
Histidine
Histone Deacetylases
Humans
Immunoprecipitation
Kinetics
Models, Chemical
Models, Molecular
Peptides
Protein Binding
Protein Conformation
Rhodamines
Sirtuin 1
Sirtuin 2
Sirtuins
Stilbenes
Substrate Specificity
Time Factors
Tumor Suppressor Protein p53