Intracellular organelles in the saga of Ca 2+ homeostasis: Different molecules for different purposes?

Department of Biomedical Sciences, University of Padova, Italy.
Cellular and Molecular Life Sciences CMLS (Impact Factor: 5.81). 10/2011; 69(7):1077-104. DOI: 10.1007/s00018-011-0845-9
Source: PubMed


An increase in the concentration of cytosolic free Ca(2+) is a key component regulating different cellular processes ranging from egg fertilization, active secretion and movement, to cell differentiation and death. The multitude of phenomena modulated by Ca(2+), however, do not simply rely on increases/decreases in its concentration, but also on specific timing, shape and sub-cellular localization of its signals that, combined together, provide a huge versatility in Ca(2+) signaling. Intracellular organelles and their Ca(2+) handling machineries exert key roles in this complex and precise mechanism, and this review will try to depict a map of Ca(2+) routes inside cells, highlighting the uniqueness of the different Ca(2+) toolkit components and the complexity of the interactions between them.

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