Structural basis for pharmacological modulation of the TRPC6 channel

Abstract

Transient receptor potential canonical (TRPC) proteins form nonselective cation channels that play physiological roles in a wide variety of cells. Despite growing evidence supporting the therapeutic potential of TRPC6 inhibition in treating pathological cardiac and renal conditions, mechanistic understanding of TRPC6 function and modulation remains obscure. Here we report cryo-EM structures of TRPC6 in both antagonist-bound and agonist-bound states. The structures reveal two novel recognition sites for the small-molecule modulators corroborated by mutagenesis data. The antagonist binds to a cytoplasm-facing pocket formed by S1-S4 and the TRP helix, whereas the agonist wedges at the subunit interface between S6 and the pore helix. Conformational changes upon ligand binding illuminate a mechanistic rationale for understanding TRPC6 modulation. Furthermore, structural and mutagenesis analyses suggest several disease-related mutations enhance channel activity by disrupting interfacial interactions. Our results provide principles of drug action that may facilitate future design of small molecules to ameliorate TRPC6-mediated diseases.

Data availability

The low pass filtered and amplitude modified 3D cryo-EM density maps for TRPC6 in complex with antagonist AM-1473 (accession code: EMD-20954) and agonist AM-0883 (accession code: EMD-20953) have been deposited in the electron microscopy data bank. Atomic coordinates for TRPC6 in complex with antagonist AM-1473 (accession code: 6UZA) and agonist AM-0883 (accession code: 6UZ8) have been deposited in the protein data bank.

The following data sets were generated

Article and author information

Author details

  1. Yonghong Bai

    Molecular Engineering, Amgen Inc, Cambridge, United States
    For correspondence
    ybai80@gmail.com
    Competing interests
    Yonghong Bai, At the time of the study YB was affiliated with Amgen Research, Amgen Inc. and has no financial interests to declare. The author has no other competing interests to declare..
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4334-0916
  2. Xinchao Yu

    Molecular Engineering, Amgen Inc, South San Francisco, United States
    For correspondence
    xyu01@amgen.com
    Competing interests
    Xinchao Yu, XY is affiliated with Amgen Research, Amgen Inc. and has no financial interests to declare. The author has no other competing interests to declare..
  3. Hao Chen

    Protein Technologies, Amgen Inc, Cambridge, United States
    Competing interests
    Hao Chen, At the time of the study HC was affiliated with Amgen Research, Amgen Inc. and has no financial interests to declare. The author has no other competing interests to declare..
  4. Daniel Horne

    Medicinal Chemistry, Amgen Inc, Cambridge, United States
    Competing interests
    Daniel Horne, At the time of the study DH was affiliated with Amgen Research, Amgen Inc. and has no financial interests to declare. The author has no other competing interests to declare..
  5. Ryan White

    Medicinal Chemistry, Amgen Inc, Cambridge, United States
    Competing interests
    Ryan White, At the time of the study RW was affiliated with Amgen Research, Amgen Inc. and has no financial interests to declare. The author has no other competing interests to declare..
  6. Xiaosu Wu

    Cardiometabolic Disorders, Amgen Inc, South San Francisco, United States
    Competing interests
    Xiaosu Wu, XW is affiliated with Amgen Research, Amgen Inc. and has no financial interests to declare. The author has no other competing interests to declare..
  7. Paul Lee

    Discovery Technologies, Amgen Inc, Thousand Oaks, United States
    Competing interests
    Paul Lee, At the time of the study PL was affiliated with Amgen Research, Amgen Inc. and has no financial interests to declare. The author has no other competing interests to declare..
  8. Yan Gu

    Protein Technologies, Amgen Inc, Cambridge, United States
    Competing interests
    Yan Gu, At the time of the study YG was affiliated with Amgen Research, Amgen Inc. and has no financial interests to declare. The author has no other competing interests to declare..
  9. Sudipa Ghimire-Rijal

    Molecular Engineering, Amgen Inc, Cambridge, United States
    Competing interests
    Sudipa Ghimire-Rijal, SGR is affiliated with Amgen Research, Amgen Inc. and has no financial interests to declare. The author has no other competing interests to declare..
  10. Daniel C-H Lin

    Cardiometabolic Disorders, Amgen Inc, South San Francisco, United States
    For correspondence
    dclin@amgen.com
    Competing interests
    Daniel C-H Lin, DCHL is affiliated with Amgen Research, Amgen Inc. and has no financial interests to declare. The author has no other competing interests to declare..
  11. Xin Huang

    Molecular Engineering, Amgen Inc, Cambridge, United States
    For correspondence
    hxin@amgen.com
    Competing interests
    Xin Huang, At the time of the study XH was affiliated with Amgen Research, Amgen Inc. and has no financial interests to declare. The author has no other competing interests to declare..

Funding

No external funding was received for this work.

Reviewing Editor

  1. László Csanády, Semmelweis University, Hungary

Publication history

  1. Received: November 4, 2019
  2. Accepted: March 7, 2020
  3. Accepted Manuscript published: March 9, 2020 (version 1)
  4. Version of Record published: March 19, 2020 (version 2)

Copyright

© 2020, Bai 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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  1. Yonghong Bai
  2. Xinchao Yu
  3. Hao Chen
  4. Daniel Horne
  5. Ryan White
  6. Xiaosu Wu
  7. Paul Lee
  8. Yan Gu
  9. Sudipa Ghimire-Rijal
  10. Daniel C-H Lin
  11. Xin Huang
(2020)
Structural basis for pharmacological modulation of the TRPC6 channel
eLife 9:e53311.
https://doi.org/10.7554/eLife.53311
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