ATP and large signaling metabolites flux through caspase-activated Pannexin 1 channels
- University of Virginia, United States
- New Jersey Medical School, United States
- National Tsing Hua University, Taiwan
Abstract
Pannexin 1 (Panx1) is a membrane channel implicated in numerous physiological and pathophysiological processes via its ability to support release of ATP and other cellular metabolites for local intercellular signaling. However, to date, there has been no direct demonstration of large molecule permeation via the Panx1 channel itself, and thus the permselectivity of Panx1 for different molecules remains unknown. To address this, we expressed, purified and reconstituted Panx1 into proteoliposomes and demonstrated that channel activation by caspase cleavage yields a dye-permeable pore that favors flux of anionic, large-molecule permeants (up to ~1 kDa). Large cationic molecules can also permeate the channel, albeit at a much lower rate. We further show that Panx1 channels provide a molecular pathway for flux of ATP and other anionic (glutamate) and cationic signaling metabolites (spermidine). These results verify large molecule permeation directly through activated Panx1 channels that can support their many physiological roles.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files (Source Data files). Source data files have been provided for Figure 1G, Figure 1 Supplement 1C, Figure 1 Supplement 2B-E, Figure 2D, Figure 2 Supplement 1, Figure 2 Supplement 2A-F, Figure 3B-I, Figure 4 B-D, Figure 4 Supplement 2B-C. Source code has been uploaded to Github: https://github.com/VolkerKirchheim/VK_TIRFsinglevesicleStep1. Data is also available on Dryad under doi:10.5061/dryad.s1rn8pk69
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Data from: Caspase-activated Pannexin 1 channels favor anionic molecules and support flux of ATP and other signaling metabolitesDryad Digital Repository, 10.5061/dryad.s1rn8pk69.
Article and author information
Author details
Adishesh K Narahari
Alex J B Kreutzberger
Funding
National Institutes of Health (P01 HL120840)
- Kodi S Ravichandran
- Mark Yeager
- Douglas Bayliss
Ministry of Science and Technology, Taiwan (108-2320-B-007-007-MY2)
- Yu-Hsin Chiu
National Institutes of Health (T32 GM007267)
- Adishesh K Narahari
University of Virginia (Whitfield-Randolph Scholarship)
- Adishesh K Narahari
National Institutes of Health (R01 HL138241)
- Paula Q Barrett
National Institutes of Health (R01 GM099490)
- Jorge E Contreras
National Institutes of Health (R01 HL48908)
- Mark Yeager
National Institutes of Health (R01 GM138532)
- Mark Yeager
National Institutes of Health (P01 GM072694)
- Lukas K Tamm
National Institutes of Health (R01 GM051329)
- Lukas K Tamm
National Institutes of Health (F30 CA236370)
- Adishesh K Narahari
National Institutes of Health (T32 GM007055)
- Adishesh K Narahari
- Christopher B Medina
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Narahari 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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ATP and large signaling metabolites flux through caspase-activated Pannexin 1 channels
eLife 10:e64787.
https://doi.org/10.7554/eLife.64787
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