Regulation of respiration in rotenone-treated tobacco cell suspension cultures.
Cells of Nicotiana tabacum L. suspension cultures were treated with the respiratory inhibitor rotenone, which specifically inhibits complex I activity of mitochondria. Rotenone retarded cell growth, as shown by decreases in fresh weight, dry weight and cell numbers on a suspension-volume basis. However, rates of the coupled respiration were higher in rotenone-treated compared to control cells when expressed on a fresh-weight basis. Rates of the rotenone-insensitive respiration increased substantially on both a fresh-weight and extractable-cellular-protein basis 24 h after rotenone treatment. ATP/ADP ratios were not significantly different between control and rotenone-treated cells. Our results indicated that cells of tobacco suspension cultures were able to maintain a slow rate of growth and adequate ATP/ADP ratios without the operation of complex I.
Zhang
Q
Q
Department of Environmental Biology, University of Adelaide, SA 5005, Australia. qisen.zhang@adelaide.edu.au
Soole
K L
KL
Wiskich
J T
JT
D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D019069:Cell Respiration / Q000187:drug effects; D002478:Cells, Cultured; D042967:Electron Transport Complex I; D003576:Electron Transport Complex IV / Q000378:metabolism; D005649:Fumarate Hydratase / Q000378:metabolism; D008293:Malates / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism; D009247:NADH, NADPH Oxidoreductases / Q000037:antagonists & inhibitors* / Q000187:drug effects / Q000378:metabolism; D010084:Oxidation-Reduction; D010085:Oxidative Phosphorylation / Q000187:drug effects; D010101:Oxygen Consumption / Q000187:drug effects; D010947:Plants, Toxic; D012402:Rotenone / Q000494:pharmacology*; D014026:Nicotiana / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D014475:Uncoupling Agents / Q000494:pharmacology*
D008293:Malates; D014475:Uncoupling Agents; D012402:Rotenone; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D009247:NADH, NADPH Oxidoreductases; D003576:Electron Transport Complex IV; D005649:Fumarate Hydratase; D042967:Electron Transport Complex I