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Published on: July 16, 2013
Cell-cell communication beyond connexins: the pannexin channels
Michael T Barbe1, Hannah Monyer, Roberto Bruzzone
1Department of Clinical Neurobiology and Interdisciplinary Center for Neuroscience, University of Heidelberg, Heidelberg, Germany.
Physiology (Bethesda, Md.)
|March 28, 2006
Summary
Cell-to-cell communication utilizes diverse proteins like innexins and connexins. Pannexins, a novel protein family, also form intercellular channels, prompting research into their evolutionary roles and functions in vivo.
Area of Science:
- Molecular Biology
- Evolutionary Biology
- Cell Biology
Background:
- Direct cell-to-cell communication is vital in multicellular organisms.
- Diverse organisms use distinct protein families (innexins, connexins) for intercellular channels.
- Pannexins represent a newly identified family of channel-forming proteins.
Purpose of the Study:
- To investigate the evolutionary relationship of pannexins to other channel proteins.
- To understand the functional contribution of pannexins to cell communication in vivo.
- To characterize the properties of mammalian pannexins, particularly pannexin1.
Main Methods:
- Comparative analysis of gene families involved in intercellular communication.
- Expression studies of pannexin genes in developing and adult mammalian brains.
- Functional characterization of pannexin1, including Ca2+-activated hemichannel formation.
Main Results:
- Pannexins form intercellular channels, distinct from innexins and connexins.
- Three pannexin genes exist in mammals, with two co-expressed in the brain.
- Pannexin1 forms Ca2+-activated hemichannels at physiological calcium levels with unique pharmacology.
Conclusions:
- Pannexins represent a significant, evolutionarily conserved component of intercellular communication.
- Pannexin1's ability to form functional hemichannels suggests a key role in cellular signaling.
- Further research is needed to fully elucidate the in vivo roles and mechanisms of pannexins.
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