Lipid-loving ANTs: molecular simulations of cardiolipin interactions and the organization of the adenine nucleotide translocase in model mitochondrial membranes
Author(s)
Type
Journal Article
Abstract
The exchange of ADP and ATP across the inner mitochondrial membrane is a fundamental cellular process. This exchange is facilitated by the adenine nucleotide translocase, the structure and function of which are critically dependent on the signature phospholipid of mitochondria, cardiolipin (CL). Here we employ multiscale molecular dynamics simulations to investigate CL interactions within a membrane environment. Using simulations at both coarse-grained and atomistic resolutions, we identify three CL binding sites on the translocase, in agreement with those seen in crystal structures and inferred from nuclear magnetic resonance measurements. Characterization of the free energy landscape for lateral lipid interaction via potential of mean force calculations demonstrates the strength of interaction compared to those of binding sites on other mitochondrial membrane proteins, as well as their selectivity for CL over other phospholipids. Extending the analysis to other members of the family, yeast Aac2p and mouse uncoupling protein 2, suggests a degree of conservation. Simulation of large patches of a model mitochondrial membrane containing multiple copies of the translocase shows that CL interactions persist in the presence of protein–protein interactions and suggests CL may mediate interactions between translocases. This study provides a key example of how computational microscopy may be used to shed light on regulatory lipid–protein interactions.
Date Issued
2016-11-15
Date Acceptance
2016-10-01
Citation
Biochemistry, 2016, 55 (45), pp.6238-6249
ISSN
1520-4995
Publisher
American Chemical Society
Start Page
6238
End Page
6249
Journal / Book Title
Biochemistry
Volume
55
Issue
45
Copyright Statement
© 2016 American Chemical Society. This is an open access article published under a Creative Commons Attribution (CC-BY) License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited.
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000388156300005&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Subjects
Science & Technology
Life Sciences & Biomedicine
Biochemistry & Molecular Biology
TIGHTLY BOUND CARDIOLIPIN
ADP/ATP CARRIER PROTEIN
GRAINED FORCE-FIELD
FREE-ENERGY
INNER MEMBRANE
UNCOUPLING PROTEIN-2
DYNAMICS SIMULATIONS
TRANSPORT MECHANISM
RESPIRATORY-CHAIN
STRUCTURAL BASIS
Publication Status
Published
Date Publish Online
2016-10-27