Mitochondrial and cytosolic ATP/ADP ratios in rat liver in vivo.
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ABSTRACT:
SUBMITTER: Schwenke WD
PROVIDER: S-EPMC1163549 | biostudies-other | 1981 Nov
REPOSITORIES: biostudies-other
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Project description:Adenosine triphosphate (ATP) is a central metabolite that plays fundamental roles as an energy transfer molecule, a phosphate donor, and a signaling molecule inside the cells. The phosphoryl group transfer potential of ATP provides a thermodynamic driving force for many metabolic reactions, and phosphorylation of both small metabolites and large proteins can serve as a regulatory modification. In the process of phosphoryl transfer from ATP, the diphosphate ADP is produced, and as a result, the ATP-to-ADP ratio is an important physiological control parameter. The ATP-to-ADP ratio is directly proportional to cellular energy charge and phosphorylation potential. Furthermore, several ATP-dependent enzymes and signaling proteins are regulated by ADP, and their activation profiles are a function of the ATP-to-ADP ratio. Finally, regeneration of ATP from ADP can serve as an important readout of energy metabolism and mitochondrial function. We, therefore, developed a genetically encoded fluorescent biosensor tuned to sense ATP-to-ADP ratios in the physiological range of healthy mammalian cells. Here, we present a protocol for using this biosensor to visualize energy status using live-cell fluorescence microscopy.
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