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The IP3 receptor-KRAP complex at the desmosomes: A new player in the apoptotic process
1KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, BE-3000 Leuven, Belgium.
Cell Calcium
|October 24, 2024
Summary
In epithelial cells, inositol trisphosphate receptors (IP3Rs) trigger calcium elevation to expel apoptotic cells. This process involves K-Ras-induced actin-interacting protein (KRAP) association with IP3Rs, revealing a novel role in apoptosis.
Area of Science:
- Cell Biology
- Molecular Biology
- Calcium Signaling
Background:
- Inositol trisphosphate receptors (IP3Rs) are calcium (Ca2+) channels in the endoplasmic reticulum, regulating cellular events including apoptosis.
- Aberrant Ca2+ signaling via IP3Rs can trigger cell death pathways, such as excessive Ca2+ release to mitochondria.
Purpose of the Study:
- To investigate the role of IP3Rs in the extrusion of apoptotic cells from epithelial monolayers.
- To elucidate the mechanism linking IP3Rs, K-Ras-induced actin-interacting protein (KRAP), and apoptosis regulation.
Main Methods:
- Utilized epithelial monolayers to study cellular responses during apoptosis.
- Investigated the association of IP3Rs with desmosomes via KRAP.
Main Results:
- Demonstrated that sustained Ca2+ elevation mediated by IP3Rs promotes the extrusion of adjacent apoptotic cells.
- Identified KRAP as a key protein linking IP3Rs to desmosomes, influencing their activity.
Conclusions:
- IP3Rs play a novel role in actively removing apoptotic cells from epithelial tissues.
- KRAP and associated proteins are critical regulators of IP3R function in the context of apoptosis and epithelial integrity.
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