Crystallography-guided discovery of carbazole-based retinoic acid-related orphan receptor gamma-t (RORγt) modulators:insights into different protein behaviors with "short" and"long" inverse agonists

• 作者: Ming-cheng Yu Feng Yang Xiao-yu Ding Nan-nan Sun Zheng-yuan Jiang Ya-fei Huang Yu-rong Yan Chen Zhu Qiong Xie Zhi-feng Chen Si-qi Guo Hua-liang Jiang Kai-xian Chen Cheng Luo Xiao-min Luo Shi-jie Chen Yong-hui Wang
• 来源期刊: 中国药理学报（英文版）
• 年，卷（期）: 2021,（9）
• 所属期刊栏目: Drug Discovery
• 页码范围: 1524-1534
• 页数: 11页
• 语种: 英文

摘要

A series of 6-substituted carbazole-based retinoic acid-related orphan receptor gamma-t (RORγt) modulators were discovered through 6-position modification guided by insights from the crystallographic profiles of the "short" inverse agonist 6.With the increase in the size of the 6-position substituents,the "short" inverse agonist 6 first reversed its function to agonists and then to"long" inverse agonists.The cocrystal structures of RORγt complexed with the representative "short" inverse agonist 6 (PDB:6LOB),the agonist 7d (PDB:6LOA) and the "long" inverse agonist 7h (PDB:6LO9) were revealed by X-ray analysis.However,minor differences were found in the binding modes of "short" inverse agonist 6 and "long" inverse agonist 7h.To further reveal the molecular mechanisms of different RORγt inverse agonists,we performed molecular dynamics simulations and found that "short" or"long" inverse agonists led to different behaviors of helixes H11,H11',and H12 of RORγt.The "short" inverse agonist 6 destabilizes H11'and dislocates H12,while the "long" inverse agonist 7h separates H11 and unwinds H12.The results indicate that the two types of inverse agonists may behave differently in downstream signaling,which may help identify novel inverse agonists with different regulatory mechanisms.