TMEM120A is a coenzyme A-binding membrane protein with structural similarities to ELOVL fatty acid elongase
Abstract
TMEM120A, also named as TACAN, is a novel membrane protein highly conserved in vertebrates and was recently proposed to be a mechanosensitive channel involved in sensing mechanical pain. Here we present the single particle cryo-EM structure of human TMEM120A which forms a tightly packed dimer with extensive interactions mediate by the N-terminal coiled coil domain (CCD), the C-terminal transmembrane domain (TMD), and the re-entrant loop between the two domains. The TMD of each TMEM120A subunit contains six transmembrane helices (TMs) and has no clear structural feature of a channel protein. Instead, the six TMs form an α-barrel with a deep pocket where a coenzyme A (CoA) molecule is bound. Intriguingly, some structural features of TMEM120A resemble those of elongase for very long-chain fatty acid (ELOVL) despite low sequence homology between them, pointing to the possibility that TMEM120A may function as an enzyme for fatty acid metabolism, rather than a mechanosensitive channel.
Data availability
The cryo-EM density map and the atomic coordinates of the human TMEM120A have been deposited in the Electron Microscopy Data Bank under accession numbers EMD-24230 and the Protein Data Bank under accession numbers 7N7P, respectively
-
Cryo-EM structure of human TMEM120AElectron Microscopy Data Bank, EMD-24230.
Article and author information
Author details
Funding
Howard Hughes Medical Institute
- Youxing Jiang
Howard Hughes Medical Institute
- Nick V Grishin
National Institute of General Medical Sciences (R35GM140892)
- Youxing Jiang
National Institute of General Medical Sciences (R35GM136370)
- Benjamin P Tu
National Institute of General Medical Sciences (GM127390)
- Nick V Grishin
Welch Foundation (I-1578)
- Youxing Jiang
Welch Foundation (I-1505)
- Nick V Grishin
National Science Foundation (1955260)
- Junmei Wang
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Xue et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
Metrics
-
- 2,723
- views
-
- 347
- downloads
-
- 27
- citations
Views, downloads and citations are aggregated across all versions of this paper published by eLife.
Citations by DOI
-
- 27
- citations for umbrella DOI https://doi.org/10.7554/eLife.71220