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arXiv · 1002.0409

Regulatory assembly of the vacuolar proton pump VOV1-ATPase in yeast cells by FLIM-FRET

Stefan Ernst·Claire Batisse·Nawid Zarrabi·Bettina Boettcher·Michael Boersch
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Abstract

We investigate the reversible disassembly of VOV1-ATPase in life yeast cells by time resolved confocal FRET imaging. VOV1-ATPase in the vacuolar membrane pumps protons from the cytosol into the vacuole. VOV1-ATPase is a rotary biological nanomotor driven by ATP hydrolysis. The emerging proton gradient is used for transport processes as well as for pH and Ca2+ homoeostasis in the cell. Activity of the VOV1-ATPase is regulated through assembly / disassembly processes. During starvation the two parts of VOV1-ATPase start to disassemble. This process is reversed after addition of glucose. The exact mechanisms are unknown. To follow the disassembly / reassembly in vivo we tagged two subunits C and E with different fluorescent proteins. Cellular distributions of C and E were monitored using a duty cycle-optimized alternating laser excitation scheme (DCO-ALEX) for time resolved confocal FRET-FLIM measurements.

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Stefan Ernst, Claire Batisse, Nawid Zarrabi, Bettina Boettcher, Michael Boersch. 2010-02-02. Regulatory assembly of the vacuolar proton pump VOV1-ATPase in yeast cells by FLIM-FRET. https://doi.org/10.1117/12.841169

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