title: Protein synthesis during oxygen conformance and severe hypoxia in the mouse muscle cell line C2C12.
abstract: Oxygen conformance can be described as the ability to reduce energy demand, and hence oxygen consumption, in response to a decline in oxygen availability without a decrease in the concentration of ATP. It has been proposed that oxygen conformance may enhance cellular survival at low oxygen concentrations. We demonstrate that non-contracting C2C12 cells, a mouse skeletal muscle cell line, are capable of oxygen conformance. Typically, we found oxygen consumption to decline by 30-40% as the concentration of oxygen was reduced from 100 microM to 10 microM. Unexpectedly, the rate of protein synthesis, a major energy consumer in the cell, did not decrease significantly during oxygen conformance. Unlike oxygen conformance, severe hypoxia (<0.5 microM) caused a 36% decline in the concentration of PCr, and under these conditions of energy stress, the rate of protein synthesis declined by 43%. We conclude that there are two distinct metabolic responses to declines in oxygen concentration in non-contracting C2C12 cells.
authors.affiliation: Department of Biochemistry, The University of Western Australia, Nedlands, W.A., Australia. parthur@cyllene.uwa.edu.au
authors.forename: P G
authors.initials: PG
authors.lastname: Arthur
authors.forename: J J
authors.initials: JJ
authors.lastname: Giles
authors.forename: C M
authors.initials: CM
authors.lastname: Wakeford
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D015687:Cell Hypoxia; D002460:Cell Line; D002470:Cell Survival; D003513:Cycloheximide; D015536:Down-Regulation; D004734:Energy Metabolism; D051379:Mice; D018482:Muscle, Skeletal / Q000378:metabolism*; D010100:Oxygen / Q000494:pharmacology*; D010101:Oxygen Consumption; D014176:Protein Biosynthesis
chemical_list: D000255:Adenosine Triphosphate; D003513:Cycloheximide; D010100:Oxygen