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Updated: Jan 6, 2026
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Proteomics to Identify Proteins Interacting with P2X2 Ligand-Gated Cation Channels
Published on: May 18, 2009
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Full-Length P2X7 Structures Reveal How Palmitoylation Prevents Channel Desensitization
Alanna E McCarthy1, Craig Yoshioka2, Steven E Mansoor1
1Vollum Institute, Oregon Health and Science University, Portland, OR 97239, USA; Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR 97239, USA.
Cell
|October 8, 2019
Summary
Structural insights into the P2X7 receptor reveal how its unique cytoplasmic domain prevents desensitization and binds nucleotides, advancing understanding of this key ion channel.
Area of Science:
- Molecular biology
- Structural biology
- Neuroscience
Background:
- P2X receptors are ATP-gated cation channels.
- The P2X7 receptor subtype is implicated in apoptosis, inflammation, and tumor progression.
- Its unique cytoplasmic domain is crucial for function but poorly understood structurally.
Purpose of the Study:
- To determine the cryoelectron microscopy structures of the full-length rat P2X7 receptor.
- To elucidate the molecular mechanisms of the P2X7 receptor's cytoplasmic domain.
- To understand how the P2X7 receptor initiates apoptosis and avoids desensitization.
Main Methods:
- Cryoelectron microscopy (cryo-EM)
- Structural determination of full-length rat P2X7 receptor in apo and ATP-bound states.
Main Results:
- Revealed the structure of the P2X7 receptor's unique cytoplasmic domain.
- Identified the C-cys anchor's role in preventing desensitization via palmitoylation.
- Discovered the cytoplasmic ballast contains a zinc ion complex and a guanosine nucleotide binding site.
Conclusions:
- The P2X7 receptor's cytoplasmic domain possesses unique structural elements critical for its function.
- These findings provide the first structural insights into the P2X7 receptor's cytoplasmic domain architecture and function.
- This structural information is vital for understanding P2X7 receptor-mediated cellular processes and developing targeted therapeutics.
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