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Updated: Jun 22, 2026
11:31
Crystal Structure of the N-terminal Domain of Ryanodine Receptor from Plutella xylostella
Published on: November 30, 2018
Homer and the ryanodine receptor.
Pierre Pouliquin1, Angela Fay Dulhunty
1Division of Molecular Bioscience, John Curtin School of Medical Research, Australian National University, PO Box 334, Canberra, ACT, 2601, Australia.
European Biophysics Journal : EBJ
|June 11, 2009
Summary
Homer proteins are identified as key ligands modulating ryanodine receptor (RyR) Ca2+ channels in muscle and neurons. Their anchoring functions and interactions with RyR complexes offer potential for diverse cellular processes.
Area of Science:
- Molecular biology
- Cellular physiology
- Neuroscience
Background:
- Homer proteins act as high-affinity ligands for ryanodine receptor (RyR) Ca2+ release channels.
- Homer proteins possess an EVH1 domain for binding proline-rich regions and a coiled-coil domain for self-association and multimerization.
- In neurons, Homer proteins anchor membrane proteins to the endoplasmic reticulum Ca2+ release channel and link membrane/cytosolic proteins to the cytoskeleton.
Purpose of the Study:
- To explore the potential role of Homer proteins in modulating cellular processes within muscle and neuronal tissues.
- To investigate the anchoring functions of Homer proteins in relation to ryanodine receptor (RyR) ion channel complexes.
- To review the known interactions of Homer proteins with RyR and associated proteins.
Main Methods:
- Literature review of existing studies on Homer proteins and ryanodine receptors.
- Analysis of consensus sequences for Homer binding within the RyR complex.
- Exploration of Homer protein functions in muscle and neuronal cell physiology.
Main Results:
- Homer proteins modulate RyR Ca2+ release channels in heart and skeletal muscle.
- Homer proteins facilitate protein anchoring to the endoplasmic reticulum and cytoskeleton in neurons.
- Consensus sequences for Homer binding are present in the RyR and its interacting proteins.
Conclusions:
- Homer proteins have significant potential to influence diverse cellular processes in muscle and neurons.
- The anchoring capabilities of Homer proteins may play a crucial role in the function of RyR channel complexes.
- Further investigation into Homer's role in muscle physiology is warranted.
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