Please use this identifier to cite or link to this item: http://repositorio.unicamp.br/jspui/handle/REPOSIP/71216
Type: Artigo de periódico
Title: Role of F1F0-ATP synthase and uncoupling protein in mitochondrial respiratory uncoupling of ripened avocado fruits
Author: Saviani, EE
da Silva, A
Martins, IS
Abstract: The present study was carried out to determine the contribution of the F-1 F-0-ATP synthase, the ATP/ADP carrier (AAC) and a putative plant uncoupling mitochondrial protein (PUMP) to the increased respiratory activity of ripened avocado fruits. We have compared the beta-subunit content of F-1 and AAC, determined by photoaffinity labelling with 8-azido-[alpha-P-32]ATP, and the transmembrane electrical potential difference (Delta Psi), established by substrate oxidation, in mitochondria isolated from pre- and postclimacteric avocado fruits. The beta-subunit content of F-1 decreased, while that of AAC did not change, with ripening. The Delta Psi established by succinate oxidation of postclimacteric avocado mitochondria was very low and could be substantially increased by oligomycin, which inhibits H+ transport through F-0, and by the purine nucleotides GTP or ATP, which are known to inhibit H+ transport through the uncoupling protein present in brown adipose tissue and potato tuber mitochondria. Oligomycin and GTP had no effect on the Delta Psi of preclimacteric avocado mitochondria. Carboxyatractyloside and bongkrekic acid, specific inhibitors of AAC, had no effect on the Delta Psi of pre- or postclimacteric avocado mitochondria. These results suggest that a PUMP-like protein may exist in mitochondria of postclimacteric avocado fruits, and that this protein and the F-0 from beta-detached ATP synthase, but not the AAC, could provide pathways for energy dissipation in ripened avocado fruit mitochondria. (C) Elsevier, Paris.
Subject: avocado fruit ripening
alternative oxidase
mitochondrial ATP synthase
plant uncoupling mitochondrial protein
photoaffinity labelling
ATP/ADP carrier
mitochondrial H+ permeability
Country: França
Editor: Gauthier-villars/editions Elsevier
Rights: fechado
Identifier DOI: 10.1016/S0981-9428(98)80005-3
Date Issue: 1998
Appears in Collections:Artigos e Materiais de Revistas Científicas - Unicamp

Files in This Item:
File Description SizeFormat 
WOS000075710700005.pdf896.87 kBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.