Back
Cryo-EM structures and functional characterization of the murine lipid scramblase TMEM16F.
Journal article

Cryo-EM structures and functional characterization of the murine lipid scramblase TMEM16F.

  • Alvadia C Department of Biochemistry, University of Zurich, Zurich, Switzerland.
  • Lim NK Department of Biochemistry, University of Zurich, Zurich, Switzerland.
  • Clerico Mosina V Department of Structural Biology at the Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, Netherlands.
  • Oostergetel GT Department of Structural Biology at the Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, Netherlands.
  • Dutzler R Department of Biochemistry, University of Zurich, Zurich, Switzerland.
  • Paulino C Department of Structural Biology at the Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, Netherlands.
Show more…
  • 2019-02-21
Published in:
  • eLife. - 2019
Cryo-EM
TMEM16F
electrophysiology
human
ion conduction
lipid scramblase
mechanism of action
molecular biophysics
mouse
structural biology
Anoctamins
Calcium
Cations, Divalent
Cryoelectron Microscopy
Ion Channels
Phospholipid Transfer Proteins
Protein Conformation
English The lipid scramblase TMEM16F initiates blood coagulation by catalyzing the exposure of phosphatidylserine in platelets. The protein is part of a family of membrane proteins, which encompasses calcium-activated channels for ions and lipids. Here, we reveal features of murine TMEM16F (mTMEM16F) that underlie its function as a lipid scramblase and an ion channel. The cryo-EM data of mTMEM16F in absence and presence of Ca2+ define the ligand-free closed conformation of the protein and the structure of a Ca2+-bound intermediate. Both conformations resemble their counterparts of the scrambling-incompetent anion channel mTMEM16A, yet with distinct differences in the region of ion and lipid permeation. In conjunction with functional data, we demonstrate the relationship between ion conduction and lipid scrambling. Although activated by a common mechanism, both functions appear to be mediated by alternate protein conformations that are at equilibrium in the ligand-bound state.
Language
  • English
Open access status
gold
Identifiers
Persistent URL
https://folia.unifr.ch/global/documents/48001
Statistics
Document views: 16 File downloads: