+Search query
-Structure paper
Title | Cryo-EM structure of the calcium homeostasis modulator 1 channel. |
---|---|
Journal, issue, pages | Sci Adv, Vol. 6, Issue 29, Page eaba8161, Year 2020 |
Publish date | Jul 17, 2020 |
Authors | Yue Ren / Tianlei Wen / Zhiqin Xi / Shunjin Li / Jing Lu / Xing Zhang / Xue Yang / Yuequan Shen / |
PubMed Abstract | Calcium homeostasis modulator 1 (CALHM1) is a voltage-gated ATP release channel that plays an important role in neural gustatory signaling and the pathogenesis of Alzheimer's disease. Here, we ...Calcium homeostasis modulator 1 (CALHM1) is a voltage-gated ATP release channel that plays an important role in neural gustatory signaling and the pathogenesis of Alzheimer's disease. Here, we present a cryo-electron microscopy structure of full-length Ca-free CALHM1 from Danio rerio at an overall resolution of 3.1 Å. Our structure reveals an octameric architecture with a wide pore diameter of ~20 Å, presumably representing the active conformation. The overall structure is substantially different from that of the isoform CALHM2, which forms both undecameric hemichannels and gap junctions. The N-terminal small helix folds back to the pore and forms an antiparallel interaction with transmembrane helix 1. Structural analysis revealed that the extracellular loop 1 region within the dimer interface may contribute to oligomeric assembly. A positive potential belt inside the pore was identified that may modulate ion permeation. Our structure offers insights into the assembly and gating mechanism of the CALHM1 channel. |
External links | Sci Adv / PubMed:32832630 / PubMed Central |
Methods | EM (single particle) |
Resolution | 3.1 Å |
Structure data | EMDB-30016, PDB-6lyg: |
Chemicals | ChemComp-NAG: |
Source |
|
Keywords | MEMBRANE PROTEIN / Octamer |