University of Leicester
Browse
Bokhovchuk et al-Biochemistry-full.pdf (4.84 MB)

The Structural Basis of Calcium-Dependent Inactivation of the Transient Receptor Potential Vanilloid 5 Channel

Download (4.84 MB)
journal contribution
posted on 2018-05-29, 08:44 authored by Fedir M. Bokhovchuk, Neil Bate, Nadezda V. Kovalevskaya, Benjamin T. Goult, Chris A. E. M. Spronk, Geerten W. Vuister
The transient receptor potential vanilloid channel subfamily member 5 (TRPV5) is a highly selective calcium ion channel predominately expressed in the kidney epithelium that plays an essential role in calcium reabsorption from renal infiltrate. In order to maintain Ca 2+ homeostasis, TRPV5 possesses a tightly regulated negative feedback mechanism, where the ubiquitous Ca 2+ binding protein calmodulin (CaM) directly binds to the intracellular TRPV5 C-terminus, thus regulating TRPV5. Here we report on the characterization of the TRPV5 C-terminal CaM binding site and its interaction with CaM at an atomistic level. We have solved the de novo solution structure of the TRPV5 C-terminus in complex with a CaM mutant, creating conditions that mimic the cellular basal Ca 2+ state. We demonstrate that under these conditions the TRPV5 C-terminus is exclusively bound to the CaM C-lobe only, while it confers conformational freedom to the CaM N-lobe. We also show that at elevated calcium levels, additional interactions between the TRPV5 C-terminus and CaM N-lobe occur, resulting in formation of a tight 1:1 complex, effectively making the N-lobe the calcium sensor. Together, these data are consistent with and support the novel model for Ca 2+ /CaM-dependent inactivation of TRPV channels as proposed by Bate and co-workers [ Bate, N., et al. (2018) Biochemistry, (57), DOI: 10.1021/acs.biochem.7b01286 ].

Funding

G.W.V. acknowledges funding during various stages of this project by the Dutch Organization of Scientific Research (NWO; 700.55.443 and 700.57.101), BBSRC (BB/J007897/1), and MRC (MR/L000555/1 and MR/P00038X/1).

History

Citation

Biochemistry, 2018, 57 (18), pp. 2623-2635

Author affiliation

/Organisation/COLLEGE OF LIFE SCIENCES/Biological Sciences/Molecular & Cell Biology

Version

  • AM (Accepted Manuscript)

Published in

Biochemistry

Publisher

American Chemical Society

issn

0006-2960

eissn

1520-4995

Copyright date

2018

Available date

2019-03-27

Publisher version

https://pubs.acs.org/doi/10.1021/acs.biochem.7b01287

Notes

Accession Codes Chemical shifts and restraints were submitted to the BMRB (accession number 34161), and the ensemble of 20 conformers were submitted to the wwPDB (accession number 5OEO).;The file associated with this record is under embargo until 12 months after publication, in accordance with the publisher's self-archiving policy. The full text may be available through the publisher links provided above.

Language

en

Usage metrics

    University of Leicester Publications

    Categories

    No categories selected

    Keywords

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC