RT info:eu-repo/semantics/article
T1 Chromaffin-cell stimulation triggers fast millimolar mitochondrial Ca2+ transients that modulate secretion
A1 Montero Zoccola, María Teresa
A1 Alonso Alonso, María Teresa
A1 Carnicero Gila, Estela María
A1 Cuchillo Ibáñez, Inmaculada
A1 Albillos, Almudena
A1 García, Antonio G.
A1 García-Sancho Martín, Francisco Javier
A1 Álvarez Martín, Javier
K1 Calcio - Efectos fisiológicos
AB Activation of calcium-ion (Ca2+) channels on the plasma membrane and on intracellular Ca2+ stores, such as theendoplasmic reticulum, generates local transient increases in the cytosolic Ca2+ concentration that induce Ca2+ uptakeby neighbouring mitochondria. Here, by using mitochondrially targeted aequorin proteins with different Ca2+ affinities,we show that half of the chromaffin-cell mitochondria exhibit surprisingly rapid millimolar Ca2+ transients uponstimulation of cells with acetylcholine, caffeine or high concentrations of potassium ions. Our results show a tightfunctional coupling of voltage-dependent Ca2+ channels on the plasma membrane, ryanodine receptors on theendoplasmic reticulum, and mitochondria. Cell stimulation generates localized Ca2+ transients, with Ca2+ concentrationsabove 20–40 mM, at these functional units. Protonophores abolish mitochondrial Ca2+ uptake and increase stimulatedsecretion of catecholamines by three- to fivefold. These results indicate that mitochondria modulate secretion bycontrolling the availability of Ca2+ for exocytosis.
PB Macmillan Magazines Ltd.
SN 1465-7392
YR 2000
FD 2000
LK http://uvadoc.uva.es/handle/10324/5970
UL http://uvadoc.uva.es/handle/10324/5970
LA eng
NO Nature Cell Biology, Febrero 2000, vol. 2, p. 57-61
NO Producción Científica
DS UVaDOC
RD 23-nov-2024