Regulation of cartilage-specific gene expression in human chondrocytes by SirT1 and nicotinamide phosphoribosyltransferase.

ABSTRACT: SirT1 is an NAD-dependent histone deacetylase that regulates gene expression, differentiation, development, and organism life span. Here we investigate the function of SirT1 in human chondrocytes derived from osteoarthritic patients. Elevation of SirT1 protein levels or activity in these chondrocytes led to a dramatic increase in cartilage-specific gene expression, whereas a reduction in SirT1 levels or activity significantly lowered cartilage gene expression. SirT1 associated with the cartilage-specific transcription factor Sox9, enhancing transcription from the collagen 2(alpha1) promoter in a Sox9-dependent fashion. Consistent with this association, SirT1 was targeted to the collagen 2(alpha1) enhancer and promoter, which in turn recruited the coactivators GCN5, PGC1alpha, and p300. Thi

SUBMITTER: Dvir-Ginzberg M 

PROVIDER: S-EPMC2605985 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature