Effects of cold exposure in vivo and uncouplers and recouplers in vitro on potato tuber mitochondria.
Effects of cold exposure in vivo and treatment with laurate, carboxyatractylate, atractylate, nucleotides, and BSA in vitro on potato tuber mitochondria have been studied. Cold exposure of tubers for 48-96 h resulted in some uncoupling that could be reversed completely by BSA and partially by ADP, ATP, UDP, carboxyatractylate, and atractylate. UDP was less effective than ADP and ATP, and atractylate was less effective than carboxyatractylate. The recoupling effects of nucleotides were absent when the nucleotides were added after carboxyatractylate. GDP, UDP, and CDP did not recouple mitochondria from either the control or the cold-exposed tubers. This indicates that the cold-induced fatty acid-mediated uncoupling in potato tuber mitochondria is partially due to the operation of the ATP/ADP antiporter. As to the plant uncoupling protein, its contribution to the uncoupling in tuber is negligible or, under the conditions used, somehow desensitized to nucleotides.
Popov
V N
VN
Department of Plant Physiology and Biochemistry, Voronezh State University, Voronezh 394693, Russia.
Markova
O V
OV
Mokhova
E N
EN
Skulachev
V P
VP
D000222:Adaptation, Physiological; D000244:Adenosine Diphosphate; D001278:Atractyloside / Q000031:analogs & derivatives*; D002352:Carrier Proteins / Q000737:chemistry / Q000378:metabolism*; D003080:Cold Temperature; D004791:Enzyme Inhibitors; D006153:Guanosine Diphosphate; D007425:Intracellular Membranes / Q000737:chemistry / Q000378:metabolism; D007473:Ion Channels; D007850:Lauric Acids; D008564:Membrane Potentials; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism*; D008928:Mitochondria / Q000737:chemistry / Q000378:metabolism; D024101:Mitochondrial Proteins; D010101:Oxygen Consumption; D012710:Serum Albumin, Bovine; D011198:Solanum tuberosum / Q000737:chemistry / Q000378:metabolism*; D000071256:Uncoupling Protein 1
D002352:Carrier Proteins; D004791:Enzyme Inhibitors; D007473:Ion Channels; D007850:Lauric Acids; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D000071256:Uncoupling Protein 1; C030358:lauric acid; D006153:Guanosine Diphosphate; D001278:Atractyloside; D012710:Serum Albumin, Bovine; D000244:Adenosine Diphosphate; C003853:carboxyatractyloside