胱天蛋白酶-1與Gasdermin D發生相互作用的結構基礎獲解析
作者:
小柯機器人發布時間:2020/6/18 16:51:48
美國凱斯西儲大學Tsan Sam Xiao課題組解析出胱天蛋白酶-1與Gasdermin D(GSDMD)發生相互作用的結構基礎。2020年6月17日,《免疫》在線發表了這一成果。
研究人員報導了人類胱天蛋白酶-1和全長小鼠GSDMD複合物的晶體結構。 除了胱天蛋白酶-1活性位點與GSDMD N和C結構域連接子接合外,胱天蛋白酶-1 L2和L2'環上的反平行β摺疊還結合了GSDMD C末端結構域的疏水口袋。該「外位點」界面除了具有自抑制作用外,還為GSDMD C末端結構域提供了一個額外的功能,即胱天蛋白酶招募模塊。
因此,這項研究揭示了胱天蛋白酶-1與GSDMD的雙界面結合,這可能適用於胱天蛋白酶的其他生理底物。
據了解,炎症胱天蛋白酶-1、4、5和11對GSDMD的識別和切割是在炎性體活化後啟動細胞焦亡的重要步驟。先前的工作已經確定了底物(例如GSDMD)中的切割位點特徵,但尚不清楚這些是否是胱天蛋白酶參與的唯一決定因素。
附:英文原文
Title: Caspase-1 Engages Full-Length Gasdermin D through Two Distinct Interfaces That Mediate Caspase Recruitment and Substrate Cleavage
Author: Zhonghua Liu, Chuanping Wang, Jie Yang, Yinghua Chen, Bowen Zhou, Derek W. Abbott, Tsan Sam Xiao
Issue&Volume: 2020-06-17
Abstract: The recognition and cleavage of gasdermin D (GSDMD) by inflammatory caspases-1, 4,5, and 11 are essential steps in initiating pyroptosis after inflammasome activation.Previous work has identified cleavage site signatures in substrates such as GSDMD,but it is unclear whether these are the sole determinants for caspase engagement.Here we report the crystal structure of a complex between human caspase-1 and thefull-length murine GSDMD. In addition to engagement of the GSDMD N- and C-domain linkerby the caspase-1 active site, an anti-parallel β sheet at the caspase-1 L2 and L2′loops bound a hydrophobic pocket within the GSDMD C-terminal domain distal to itsN-terminal domain. This 「exosite」 interface endows an additional function for theGSDMD C-terminal domain as a caspase-recruitment module besides its role in autoinhibition.Our study thus reveals dual-interface engagement of GSDMD by caspase-1, which maybe applicable to other physiological substrates of caspases.
DOI: 10.1016/j.immuni.2020.06.007
Source: https://www.cell.com/immunity/fulltext/S1074-7613(20)30237-5