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Imaging Local Ca2+ Signals in Cultured Mammalian Cells
Published on: March 3, 2015
Local Ca2+ signals in cellular signalling
1CNRS UMR 5017 - Signalisation et Interactions Cellulaires, Université Bordeaux 2, 146 rue Léo Saignat, 33076 Bordeaux, France. nathalie.macrez@umr5017.u-bordeaux2.fr
Current Molecular Medicine
|April 23, 2004
Summary
Cellular calcium (Ca2+) signals, including local rises and propagated waves, are crucial for diverse cell functions. Understanding the molecular basis of these Ca2+ signals, particularly local events, is key to cellular regulation.
Area of Science:
- Cellular Biology
- Molecular Physiology
- Biochemistry
Background:
- Calcium ions (Ca2+) act as critical intracellular second messengers.
- Diverse Ca2+ signal patterns, including local and propagated signals, regulate cellular functions.
- Ca2+ signal plasticity is essential for cellular adaptation, affecting processes from contraction to proliferation and cell death.
Purpose of the Study:
- To review the molecular mechanisms underlying local Ca2+ release events.
- To discuss the roles of different Ca2+ channels, particularly ryanodine receptors (RyRs) and inositol 1,4,5-trisphosphate receptors (InsP3Rs).
- To explore how local Ca2+ signaling contributes to cellular functions in physiological and pathological states.
Main Methods:
- Review of scientific literature on Ca2+ signaling.
- Analysis of molecular structures and locations of Ca2+ signaling molecules.
- Discussion of Ca2+ release channels (RyRs, InsP3Rs) and their regulation.
Main Results:
- Local Ca2+ signals, such as Ca2+ spikes, sparks, and puffs, are highly specific and confined.
- These elementary Ca2+ events are mediated by RyRs and InsP3Rs and control cellular excitability.
- Regulation of local Ca2+ release involves second messengers, channel-associated proteins, and endoplasmic reticulum Ca2+ content.
Conclusions:
- Local Ca2+ signaling provides spatial and temporal versatility for specific cellular responses.
- Understanding the molecular basis of RyRs and InsP3Rs is vital for deciphering localized Ca2+ responses.
- Control of local cellular Ca2+ is fundamental to cellular functions in health and disease.
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