8BC1 image
Entry Detail
PDB ID:
8BC1
EMDB ID:
Title:
Cryo-EM Structure of Ca2+-bound mTMEM16F F518A_Q623A mutant in GDN
Biological Source:
Source Organism:
Host Organism:
PDB Version:
Deposition Date:
2022-10-14
Release Date:
2022-11-16
Method Details:
Experimental Method:
Resolution:
2.93 Å
Aggregation State:
PARTICLE
Reconstruction Method:
SINGLE PARTICLE
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:Anoctamin-6,mTMEM16F
Mutations:F518A,Q623A
Chain IDs:A, B
Chain Length:975
Number of Molecules:2
Biological Source:Mus musculus
Ligand Molecules
Primary Citation
Structural basis for the activation of the lipid scramblase TMEM16F.
Nat Commun 13 6692 6692 (2022)
PMID: 36335104 DOI: 10.1038/s41467-022-34497-x

Abstact

TMEM16F, a member of the conserved TMEM16 family, plays a central role in the initiation of blood coagulation and the fusion of trophoblasts. The protein mediates passive ion and lipid transport in response to an increase in intracellular Ca2+. However, the mechanism of how the protein facilitates both processes has remained elusive. Here we investigate the basis for TMEM16F activation. In a screen of residues lining the proposed site of conduction, we identify mutants with strongly activating phenotype. Structures of these mutants determined herein by cryo-electron microscopy show major rearrangements leading to the exposure of hydrophilic patches to the membrane, whose distortion facilitates lipid diffusion. The concomitant opening of a pore promotes ion conduction in the same protein conformation. Our work has revealed a mechanism that is distinct for this branch of the family and that will aid the development of a specific pharmacology for a promising drug target.

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Primary Citation of related structures