Mechanistic insights into intramembrane proteolysis by E. coli site-2 protease homolog RseP

• DOI: 10.1126/sciadv.abp9011
• Publication Date: 2022-08-24T17:57:32Z
• Authors: Yuki Imaizumi; Kazunori Takanuki; Takuya Miyake; Mizuki Takemoto; Kunio Hirata; Mika Hirose; Rika Oi; Tatsuya Kobayashi; Kenichi Miyoshi; Rie Aruga; Tatsuhiko Yokoyama; Shizuka Katagiri; Hiroaki Matsuura; Kenji Iwasaki; Takayuki Kato; Mika K. Kaneko; Yukinari Kato; Michiko Tajiri; Satoko Akashi; Osamu Nureki; Yohei Hizukuri; Yoshinori Akiyama; Terukazu Nogi
• Keywords: Proteolysis; Cleave; Cleavage (geology); Conformational change

Site-2 proteases are a conserved family of intramembrane that cleave transmembrane substrates to regulate signal transduction and maintain proteostasis. Here, we elucidated crystal structures inhibitor-bound forms bacterial site-2 including Escherichia coli RseP. Structure-based chemical modification cross-linking experiments indicated the RseP domains surrounding active center undergo conformational changes expose substrate-binding site, suggesting has gating mechanism substrate entry. Furthermore, mutational analysis suggests electrostatic linkage between peripheral membrane-associated mediates changes. In vivo cleavage assays also support helix is unwound by strand addition β sheet clamped asparagine residue at for efficient cleavage. This underlying binding, i.e., unwinding clamping, appears common across distinct families segments.