Sequence and structural conservation reveal fingerprint residues in TRP channels
Abstract
TRP proteins are a large family of cation-selective channels, surpassed in variety only by voltage-gated potassium channels. Detailed molecular mechanisms governing how membrane voltage, ligand binding, or temperature can induce conformational changes promoting the open state in TRP channels are still a matter of debate. Aiming to unveil distinctive structural features common to the transmembrane domains within the TRP family, we performed phylogenetic reconstruction, sequence statistics, and structural analysis over a large set of TRP channel genes. Here we report an exceptionally conserved set of residues. This fingerprint is composed of twelve residues localized at equivalent three-dimensional positions in TRP channels from the different subtypes. Moreover, these amino acids are arranged in three groups, connected by a set of aromatics located at the core of the transmembrane structure. We hypothesize that differences in the connectivity between these different groups of residues harbors the apparent differences in coupling strategies used by TRP subgroups.
Data availability
Sequences, MSA and phylogenetic reconstruction data analyzed during this study are are available in Dryad database: https://doi.org/10.5061/dryad.k6djh9w75Code for analysis of Aromatic Core is available in Github database:https://github.com/brauchilab/ProteinCoreCluster
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Sequence conservation and structural features that are common within TRP channelsDryad Digital Repository, doi:10.5061/dryad.k6djh9w75.
Article and author information
Author details
Funding
Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT 3140233)
- Charlotte K Colenso
Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT 1191868)
- Sebastian E Brauchi
Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT 1210471)
- Juan C Opazo
Agencia Nacional de Investigación y Desarrollo (Millennium Science Initiative Program #NC160011)
- Juan C Opazo
- Sebastian E Brauchi
National Institutes of Health (R01GM093290,S10OD020095,and R01GM131048)
- Vincenzo Carnevale
National Science Foundation (IOS-1934848)
- Vincenzo Carnevale
National Science Foundation (1625061)
- Vincenzo Carnevale
U.S. Army (Research Laboratory W911NF-16-2-0189)
- Vincenzo Carnevale
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Cabezas-Bratesco 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.
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