A model-independent algorithm to derive Ca2+ fluxes underlying local cytosolic Ca2+ transients

• Autores: Ventura, A.C.; Bruno, L.; Demuro, A.; Parker, I.; Dawson, S.P.
• Año de publicación: 2005
• Idioma: inglés
• Tipo de recurso: artículo
• Fuente: Biophys. J. 2005;88(4):2403-2421
• Materia: adenosine triphosphatase (calcium); calcium channel; calcium ion; voltage gated calcium channel; algorithm; article; calcium binding; calcium cell level; calcium current; calcium signaling; calcium transport; cytosol; diffusion; fluorescence; mathematical analysis; model
• Institución: Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales

Local intracellular Ca2+ signals result from Ca2+ flux into the cytosol through individual channels or clusters of channels. To gain a mechanistic understanding of these events we need to know the magnitude and spatial distribution of the underlying Ca2+ flux. However, this is difficult to infer from fluorescence Ca2+ images because the distribution of Ca2+-bound dye is affected by poorly characterized processes including diffusion of Ca2+ ions, their binding to mobile and immobile buffers, and sequestration by Ca2+ pumps. Several methods have previously been proposed to derive Ca2+ flux from fluorescence images, but all require explicit knowledge or assumptions regarding these processes. We now present a novel algorithm that requires few assumptions and is largely model-independent. By testing the algorithm with both numerically generated image data and experimental images of sparklets resulting from Ca2+ flux through individual voltage-gated channels, we show that it satisfactorily reconstructs the magnitude and time course of the underlying Ca2+ currents. © 2005 by the Biophysical Society.
Fil:Ventura, A.C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Bruno, L. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Dawson, S.P. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.