National Natural Science Foundation of China (NSFC)
21532004, 31570733
中国
引用
ジャーナル: Sci Adv / 年: 2020 タイトル: Molecular insights into the human CLC-7/Ostm1 transporter. 著者: Sensen Zhang / Yang Liu / Bing Zhang / Jun Zhou / Tianyu Li / Zhiqiang Liu / Yang Li / Maojun Yang / 要旨: CLC family proteins translocate chloride ions across cell membranes to maintain the membrane potential, regulate the transepithelial Cl transport, and control the intravesicular pH among different ...CLC family proteins translocate chloride ions across cell membranes to maintain the membrane potential, regulate the transepithelial Cl transport, and control the intravesicular pH among different organelles. CLC-7/Ostm1 is an electrogenic Cl/H antiporter that mainly resides in lysosomes and osteoclast ruffled membranes. Mutations in human CLC-7/Ostm1 lead to lysosomal storage disorders and severe osteopetrosis. Here, we present the cryo-electron microscopy (cryo-EM) structure of the human CLC-7/Ostm1 complex and reveal that the highly glycosylated Ostm1 functions like a lid positioned above CLC-7 and interacts extensively with CLC-7 within the membrane. Our complex structure reveals a functionally crucial domain interface between the amino terminus, TMD, and CBS domains of CLC-7. Structural analyses and electrophysiology studies suggest that the domain interaction interfaces affect the slow gating kinetics of CLC-7/Ostm1. Thus, our study deepens understanding of CLC-7/Ostm1 transporter and provides insights into the molecular basis of the disease-related mutations.