Nephronectin expression is regulated by SMAD signaling in osteoblast-like MC3T3-E1 cells

作者：Tsukasaki Masayuki; Yamada Atsushi^*; Yoshimura Kentaro; Miyazono Agasa; Yamamoto Matsuo; Takami Masamichi; Miyamoto Yoichi; Morimura Naoko; Kamijo Ryutaro

来源：Biochemical and Biophysical Research Communications, 2012, 425(2): 390-392.

DOI：10.1016/j.bbrc.2012.07.106

• Nephronectin
• Alk5
• SMAD

Nephronectin (Npnt) is an extracellular matrix protein known to be a ligand for the integrin alpha 8 beta 1. We previously demonstrated that Npnt expression was suppressed by TGF-beta through ERK1/2 and JNK in osteoblasts. In this study, we found that inhibition of a TGF-beta type I receptor (TGF-beta R1, Alk5) by a specific inhibitor {2-[3-(6-Methylpyridin-2-yl)-1H-pyrazol-4-yl]-1,5-naphthyridine} strongly induced Npnt expression in osteoblast-like MC3T3-E1 cells. The Alk5 inhibitor-induced increase of Npnt expression occurred in both time- and dose-dependent manners, while that expression was also induced by introduction of an siRNA for Smad2, a central intracellular mediator of TGF-beta, signaling. These results suggest that the expression of Npnt is regulated by the Alk5-SMAD signaling pathway in osteoblasts.

• 出版日期2012-8-24