Horbelt Daniel, Boergermann Jan H, Chaikuad Apirat, Alfano Ivan, Williams Eleanor, Lukonin Ilya, Timmel Tobias, Bullock Alex N, Knaus Petra
From the Institute for Chemistry-Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany.
the Structural Genomics Consortium, University of Oxford, Oxford OX3 7DQ, United Kingdom, and.
J Biol Chem. 2015 Feb 6;290(6):3390-404. doi: 10.1074/jbc.M114.604397. Epub 2014 Nov 3.
GDF8, or myostatin, is a member of the TGF-β superfamily of secreted polypeptide growth factors. GDF8 is a potent negative regulator of myogenesis both in vivo and in vitro. We found that GDF8 signaling was inhibited by the small molecule ATP competitive inhibitors dorsomorphin and LDN-193189. These compounds were previously shown to be potent inhibitors of BMP signaling by binding to the BMP type I receptors ALK1/2/3/6. We present the crystal structure of the type II receptor ActRIIA with dorsomorphin and demonstrate that dorsomorphin or LDN-193189 target GDF8 induced Smad2/3 signaling and repression of myogenic transcription factors. As a result, both inhibitors rescued myogenesis in myoblasts treated with GDF8. As revealed by quantitative live cell microscopy, treatment with dorsomorphin or LDN-193189 promoted the contractile activity of myotubular networks in vitro. We therefore suggest these inhibitors as suitable tools to promote functional myogenesis.
生长分化因子8（GDF8），即肌肉生长抑制素，是分泌型多肽生长因子TGF-β超家族的成员。GDF8在体内和体外都是肌生成的有效负调节因子。我们发现小分子ATP竞争性抑制剂多斯莫尔啡（dorsomorphin）和LDN - 193189可抑制GDF8信号传导。这些化合物先前已被证明通过与骨形态发生蛋白（BMP）I型受体ALK1/2/3/6结合而成为BMP信号的有效抑制剂。我们展示了多斯莫尔啡与II型受体激活素受体IIA（ActRIIA）的晶体结构，并证明多斯莫尔啡或LDN - 193189靶向GDF8诱导的Smad2/3信号传导以及对肌源性转录因子的抑制。结果，两种抑制剂都挽救了用GDF8处理的成肌细胞中的肌生成。如定量活细胞显微镜观察所示，多斯莫尔啡或LDN - 193189处理可促进体外肌管网络的收缩活性。因此，我们建议将这些抑制剂作为促进功能性肌生成的合适工具。
