Biophysics of Active Vesicle Transport, an Intermediate Step That Couples Excitation and Exocytosis of Serotonin in the Neuronal Soma
Por:
De-Miguel F.F., Santamaría-Holek I., Noguez P., Bustos C., Hernández-Lemus E., Rubí J.M.
Publicada:
3 oct 2012
Resumen:
Transmitter exocytosis from the neuronal soma is evoked by brief trains of high frequency electrical activity and continues for several minutes. Here we studied how active vesicle transport towards the plasma membrane contributes to this slow phenomenon in serotonergic leech Retzius neurons, by combining electron microscopy, the kinetics of exocytosis obtained from FM1-43 dye fluorescence as vesicles fuse with the plasma membrane, and a diffusion equation incorporating the forces of local confinement and molecular motors. Electron micrographs of neurons at rest or after stimulation with 1 Hz trains showed cytoplasmic clusters of dense core vesicles at 1.5+/-0.2 and 3.7+/-0.3 mu m distances from the plasma membrane, to which they were bound through microtubule bundles. By contrast, after 20 Hz stimulation vesicle clusters were apposed to the plasma membrane, suggesting that transport was induced by electrical stimulation. Consistently, 20 Hz stimulation of cultured neurons induced spott
Filiaciones:
De-Miguel F.F.:
Univ Nacl Autonoma Mexico, Inst Fisiol Celular, Mexico City 04510, DF, Mexico
Santamaría-Holek I.:
Univ Nacl Autonoma Mexico, UMJ Fac Ciencias, Queretaro, Mexico
Noguez P.:
Univ Nacl Autonoma Mexico, Inst Fisiol Celular, Mexico City 04510, DF, Mexico
Bustos C.:
Univ Nacl Autonoma Mexico, Inst Fisiol Celular, Mexico City 04510, DF, Mexico
Hernández-Lemus E.:
Departamento de Genómica Computacional, Instituto Nacional de Medicina Genómica, Mexico City, Mexico
Rubí J.M.:
Facultat de Física, Universitat de Barcelona, Barcelona, Spain
Gold
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