Proteomic identification of ADAM12 as a regulator for TGF-?1-induced differentiation of human mesenchymal stem cells to smooth muscle cells.

ABSTRACT: Transforming growth factor-?1 (TGF-?1) induces the differentiation of human adipose tissue-derived mesenchymal stem cells (hASCs) into smooth muscle cells. Lipid rafts are cholesterol-rich microdomains in cell membranes that reportedly play a key role in receptor-mediated signal transduction and cellular responses. In order to clarify whether lipid rafts are involved in TGF-?1-induced differentiation of hASCs into smooth muscle cells, we analyzed the lipid raft proteome of hASCs.Pretreatment of hASCs with the lipid raft disruptor methyl-?-cyclodextrin abrogated TGF-?1-induced expression of ?-smooth muscle actin, a smooth muscle cell marker, suggesting a pivotal role of lipid rafts in TGF-?1-induced differentiation of hASCs to smooth muscle cells. Sucrose density gradient centrifugation along with a shotgun proteomic strategy using liquid chromatography-tandem mass spectrometry identified 1002 individual proteins as the lipid raft proteome, and 242 of these were induced by TGF-?1 treatment. ADAM12, a disintegrin and metalloproteases family member, was identified as the most highly up-regulated protein in response to TGF-?1 treatment. TGF-?1 treatment of hASCs stimulated the production of both ADAM12 protein and mRNA. Silencing of endogenous ADAM12 expression using lentiviral small hairpin RNA or small interfering RNA abrogated the TGF-?1-induced differentiation of hASCs into smooth muscle cells.These results suggest a pivotal role for lipid raft-associated ADAM12 in the TGF-?1-induced differentiation of hASCs into smooth muscle cells.

SUBMITTER: Kim YM 

PROVIDER: S-EPMC3396647 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature