Zearalenone-induced uncoupling in plant mitochondria is sensitive to 6-ketocholestanol.
Zearalenone (F-2) is a mycotoxin which acts as a protonophoric uncoupler in plant mitochondria [Macri, F. and Vianello, A., (1990) J. Plant Physiol. 136, 754-757]. In the present paper, the mechanism of F-2-induced uncoupling in pea mitochondria was studied. The uncoupling by F-2 was partially reversed by 6-ketocholestanol (kCh) under conditions in which kCh completely reversed the FCCP-induced uncoupling and almost did not affect the palmitate-induced uncoupling. Recoupling effects of carboxyatractylate, ADP and cyclosporin A were small and could not essentially decrease the kCh-insensitive part of F-2-induced uncoupling. It is suggested that a protein, mediating kCh-sensitive uncoupling, is involved in the F-2 effect in plant mitochondria.
Macri
F
F
Department of Biology and Agro-industrial Economics, University of Udine, Italia.
Vianello
A
A
Braidot
E
E
Petrussa
E
E
Mokhova
E N
EN
D001278:Atractyloside / Q000031:analogs & derivatives / Q000494:pharmacology; D002259:Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004968:Estrogens, Non-Steroidal / Q000494:pharmacology; D018698:Glutamic Acid / Q000494:pharmacology; D007653:Ketocholesterols / Q000378:metabolism / Q000494:pharmacology*; D008564:Membrane Potentials / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects*; D019308:Palmitic Acid / Q000494:pharmacology; D010944:Plants / Q000187:drug effects* / Q000648:ultrastructure; D014475:Uncoupling Agents / Q000494:pharmacology*; D015025:Zearalenone / Q000494:pharmacology*
D004968:Estrogens, Non-Steroidal; D007653:Ketocholesterols; D014475:Uncoupling Agents; D001278:Atractyloside; C063833:6-ketocholestanol; D019308:Palmitic Acid; D002259:Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone; D018698:Glutamic Acid; D015025:Zearalenone; C003853:carboxyatractyloside