Structural basis for functional interactions in dimers of SLC26 transporters

  • The SLC26 family of transporters maintains anion equilibria in all kingdoms of life. The family shares a 7 + 7 transmembrane segments inverted repeat architecture with the SLC4 and SLC23 families, but holds a regulatory STAS domain in addition. While the only experimental SLC26 structure is monomeric, SLC26 proteins form structural and functional dimers in the lipid membrane. Here we resolve the structure of an SLC26 dimer embedded in a lipid membrane and characterize its functional relevance by combining PELDOR/DEER distance measurements and biochemical studies with MD simulations and spin-label ensemble refinement. Our structural model reveals a unique interface different from the SLC4 and SLC23 families. The functionally relevant STAS domain is no prerequisite for dimerization. Characterization of heterodimers indicates that protomers in the dimer functionally interact. The combined structural and functional data define the framework for a mechanistic understanding of functional cooperativity in SLC26 dimers.
Author:Yung-Ning ChangORCiDGND, Eva A. JaumannGND, Katrin ReichelGND, Julia Hartmann, Dominik OliverORCiDGND, Gerhard HummerORCiD, Benesh JosephORCiDGND, Eric R. GeertsmaORCiD
Parent Title (German):Nature Communications
Publisher:Nature Publishing Group UK
Place of publication:London
Document Type:Article
Date of Publication (online):2019/05/02
Date of first Publication:2019/05/02
Publishing Institution:Universitätsbibliothek Johann Christian Senckenberg
Release Date:2023/06/15
Issue:Article number: 2032
Page Number:10
Biochemie, Chemie und Pharmazie
Dewey Decimal Classification:5 Naturwissenschaften und Mathematik / 57 Biowissenschaften; Biologie / 570 Biowissenschaften; Biologie
Licence (German):License LogoCreative Commons - Namensnennung 4.0