Non-inositol 1,4,5-trisphosphate (IP3) receptor IP3-binding proteins
1Department of Physiology, University College Cork, Western Gateway Building, Western Road, Cork T12 XF62, Ireland.
Biochimica Et Biophysica Acta. Molecular Cell Research
|April 3, 2023
Summary
Myo-D-inositol 1,4,5-trisphosphate (IP3) may interact with proteins beyond IP3 receptors. This study identified 26 diverse proteins, including enzymes and ion channels, that bind IP3, suggesting broader roles in cell signaling.
Area of Science:
- Cellular Biology
- Molecular Signaling
- Biochemistry
Background:
- Myo-D-inositol 1,4,5-trisphosphate (IP3) is traditionally known as a second messenger that gates IP3 receptor (IP3R) Ca2+ channels.
- Emerging evidence suggests IP3 may interact with non-IP3R proteins, hinting at broader cellular functions.
Purpose of the Study:
- To investigate the potential for IP3 to interact with proteins other than IP3 receptors.
- To identify novel IP3-binding proteins and explore their implications in cellular signaling pathways.
Main Methods:
- A comprehensive search of the Protein Data Bank was conducted using the term "IP3".
- Protein structures complexed with IP3 were analyzed for interactions with the carbon-1 phosphate of IP3.
- The identified structures were categorized to understand the diversity of IP3-interacting proteins.
Main Results:
- Out of 203 retrieved protein structures, 49 were complexed with IP3.
- Analysis focused on IP3's carbon-1 phosphate interaction, reducing the list to 35 structures.
- Nine of these were IP3 receptors; the remaining 26 included enzymes, signal transducers, cytoskeletal proteins, and the TRPV4 ion channel.
Conclusions:
- IP3 interacts with a diverse range of proteins beyond its canonical receptors.
- These novel interactions suggest IP3 plays a more extensive role in cellular signaling and function.
- Further research into these non-IP3R interactions is warranted to fully elucidate IP3's cellular roles.
Keywords:
Ligand-protein interactionMyo-D-inositol 1,4,5-trisphosphateProtein structureSignal transductionMore Related Videos
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