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Controllable Ion Channel Expression through Inducible Transient Transfection
Published on: February 17, 2017
A novel capacitative calcium entry channel expressed in excitable cells
S Philipp1, J Hambrecht, L Braslavski
1Institut für und Toxikologie der Universität des Saarlandes, Homburg/Saar, Germany. stephan.philipp@med-rz.uni-sb.de
The EMBO Journal
|August 4, 1998
Summary
Researchers discovered TRP5, a novel calcium channel crucial for cellular calcium regulation. This capacitative calcium entry (CCE) channel is activated by calcium store depletion and plays a role in neuronal calcium homeostasis.
Area of Science:
- Molecular Biology
- Neuroscience
- Cell Physiology
Background:
- Capacitative calcium entry (CCE) is a key mechanism for calcium influx into cells.
- Mammalian homologues of Drosophila transient receptor potential (TRP) proteins are involved in various cellular functions.
- Understanding novel calcium channels is vital for comprehending cellular calcium homeostasis.
Purpose of the Study:
- To identify and characterize a novel CCE channel, TRP5.
- To investigate the structure, expression, and functional properties of TRP5.
- To determine the role of TRP5 in neuronal calcium regulation.
Main Methods:
- Cloning and expression of the TRP5 gene.
- Electrophysiological recordings (e.g., inward rectifying currents).
- Calcium imaging using fura-2 fluorescence ratio measurements.
- Analysis of TRP5 transcript expression in brain tissues.
Main Results:
- TRP5 forms ion channels primarily permeable to Ca2+.
- TRP5 channels are activated by intracellular calcium store depletion.
- TRP5-mediated calcium entry is dependent on extracellular calcium concentration.
- TRP5 transcripts are predominantly expressed in specific brain regions, including the olfactory bulb, cerebellum, and hippocampus.
Conclusions:
- TRP5 is a novel capacitative calcium entry channel.
- TRP5 functions in excitable cells and contributes to neuronal calcium homeostasis.
- The discovery of TRP5 expands the understanding of TRP channel family and calcium signaling pathways.
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