HSP70 decreases receptor-dependent phosphorylation of Smad2 and blocks TGF-β-induced epithelial-mesenchymal transition

a.
College of Life Sciences, Hebei University, Baoding 071002, China
b.
State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China

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Corresponding author: E-mail address: qiangwang@ioz.ac.cn (Qiang Wang)

摘要

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Abstract: Smad2 and Smad3, the intracellular mediators of transforming growth factor β (TGF-β) signaling, are directly phosphorylated by the activated type I receptor kinase, and then shuttle from the cytoplasm into the nucleus to regulate target gene expression. Here, we report that the 70-kDa heat-shock protein (HSP70) interacts with Smad2 and decreases TGF-β signal transduction. Ectopic expression of HSP70 prevents receptor-dependent phosphorylation and nuclear translocation of Smad2, and blocks TGF-β-induced epithelial-mesenchymal transition (EMT) in HaCat cells. Our findings reveal an essential role of HSP70 in TGF-β-induced epithelial-mesenchymal transition (EMT) by impeding Smad2 phosphorylation.
- TGF-β /
- HSP70 /
- Smad2 /
- EMT

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参考文献(22)

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