Role of endoplasmic reticulum stress signaling in terminal differentiation of myoblasts

活性ATF6过表达可诱导成肌细胞凋亡。ATF6上调WW结构域结合蛋白1(WBP1)，发现其具有促凋亡作用。活性ATF6或WBP1的过表达引起抗凋亡蛋白，髓细胞白血病序列1（Mcl-1）的特异性降低。内质网应激的细胞发生凋亡，WBP1上调，Mcl-1降低。这些结果表明，ATF6通过上调WBP1特异性降低Mcl-1水平介导细胞凋亡。

Overexpression of active ATF6 induces apoptosis in myoblast cells. ATF6 up-regulated WW domain binding protein 1(WBP1), which was found to be proapoptotic. Overexpression of active ATF6 or WBP1 caused a specific decrease in an antiapoptotic protein, myeloid cell leukemia sequence 1(Mcl-1). Cells treated with ER stressors underwent apoptosis and exhibited an up-regulation of WBP1 and decreased Mcl-1.These results suggest that ATF6 mediates apoptosis via specific reduction of Mcl-1 levels through the up-regulation of WBP1.