Du 2015 J Biol Chem
|Du J, Rountree A, Cleghorn WM, Contreras L, Lindsay KJ, Sadilek M, Gu H, Djukovic D, Raftery D, Satrustegui J, Kanow M, Chan L, Tsang SH, Sweet IR, Hurley JB (2015) Phototransduction influences metabolic flux and nucleotide metabolism in mouse retina. J Biol Chem 291:4698-710.|
Abstract: Production of energy in a cell must keep pace with demand. Photoreceptors use ATP to maintain ion gradients in darkness, whereas in light they use it to support phototransduction. Matching production with consumption can be accomplished by coupling production directly to consumption. Alternatively, production can be set by a signal that anticipates demand. In this report we investigate the hypothesis that signaling through phototransduction controls production of energy in mouse retinas. We found that respiration in mouse retinas is not coupled tightly to ATP consumption. By analyzing metabolic flux in mouse retinas, we also found that phototransduction slows metabolic flux through glycolysis and through intermediaes of the citric acid cycle. We also evaluated the relative contributions of regulation of the activities of alpha-Ketoglutarate Dehydrogenase and the Aspartate-Glutamate Carrier 1. In addition, a comprehensive analysis of the retinal metabolome showed that phototransduction also influences steady-state concentrations of 5'GMP, ribose-5-phosphate, ketone bodies and purines.
• Keywords: Anaerobic metabolism, Calcium, Mitochondria, Photoreceptor, Phototransduction, Retina, Tissue slice, Pancreatic islets
Labels: MiParea: Respiration
Organism: Mouse Tissue;cell: Nervous system, Islet cell;pancreas;thymus Preparation: Isolated mitochondria
Regulation: ADP, Substrate Coupling state: LEAK, ROUTINE, OXPHOS, ET Pathway: N, ROX HRR: Oxygraph-2k, O2k-Fluorometer, Ca