Local Ca2+ signals in cellular signalling.

1. Curr Mol Med. 2004 May;4(3):263-75.

Local Ca2+ signals in cellular signalling.

Macrez N(1), Mironneau J.

Author information:
(1)CNRS UMR 5017 – Signalisation et Interactions Cellulaires, Université Bordeaux
2, 146 rue Léo Saignat, 33076 Bordeaux, France.

Local Ca2+ rises and propagated Ca2+ signals represent different patterns that
are differentially decoded for fine tuning cellular signalling. This Ca2+
concentration plasticity is absolutely required to allow adaptation to different
needs of the cells ranging from contraction or increased learning to
proliferation and cell death. A wide diversity of molecular structures and
specific location of Ca2+ signalling molecules confer spatial and temporal
versatility to the Ca2+ changes allowing specific cellular responses to be
elicited. Various types of local Ca2+ signals have been described. Ca2+ spikes
correspond to Ca2+ signals spanning several micrometers but displaying limited
propagation into a cell leading to regulation of cellular functions in one
particular zone of this cell. This is of particular relevance in cells presenting
distinct morphological specializations, i.e. apical versus basal sites or
dendritic versus somatic/axonal sites. More stereotyped elementary Ca2+ events
(denominated Ca2+ sparks or Ca2+ puffs depending on the type of endoplasmic
reticulum Ca2+ release channel involved) are highly confined and non-propagated
Ca2+ rises which are observed in the close neighbouring of the Ca2+ channels.
These elementary Ca2+ events play a major role in controlling cellular
excitability. Elementary Ca2+ events involve Ca2+ release channels such as the
ryanodine receptors (RyRs) and the inositol 1,4,5-trisphosphate receptors
(InsP3Rs). The molecular bases underlying the various local Ca2+ release events
will be discussed by reviewing the channels and particularly the different
isoforms of RyRs and InsP3Rs and their role in inducing localized Ca2+ responses.
These calcium release events are controlled by various second messengers and are
regulated by Ca2+ channel-associated proteins, intra-luminal Ca2+ content of the
endoplasmic reticulum (ER) and other Ca2+ organelles. We will discuss on how the
control of local cellular Ca2+ content may account for cellular functions in
physiological and physiopathological conditions.

DOI: 10.2174/1566524043360762
PMID: 15101684 [Indexed for MEDLINE]

Auteurs Bordeaux Neurocampus