Differential feedback regulation of ethylene biosynthesis in pulp and peel tissues of banana fruit.
The feedback regulation of ethylene biosynthesis in banana [Musa sp. (AAA group, Cavendish subgroup) cv. Grand Nain] fruit was investigated in an attempt to clarify the opposite effect of 1-methylcyclopropene (1-MCP), an ethylene action inhibitor, before and after the onset of ripening. 1-MCP pre-treatment completely prevented the ripening-induced effect of propylene in pre-climacteric banana fruit, whereas treatment after the onset of ripening stimulated ethylene production. In pre-climacteric fruit, higher concentrations of propylene suppressed ethylene production more strongly, despite their earlier ethylene-inducing effect. Exposure of the fruit ripened by propylene to 1-MCP increased ethylene production concomitantly with an increase in 1-aminocyclopropane-1-carboxylate (ACC) synthase activity and ACC content, and prevented a transient decrease in MA-ACS1 transcripts in the pulp tissues. In contrast, in the peel of ripening fruit, 1-MCP prevented the increase in ethylene production and subsequently the ripening process by reduction of the increase in MA-ACS1 and MA-ACO1 transcripts and of ACC synthase and ACC oxidase activities. These results suggest that ethylene biosynthesis in ripening banana fruit may be controlled negatively in the pulp tissue and positively in the peel tissue. This differential regulation by ethylene in pulp and peel tissues was also observed for MA-PL, MA-Exp, and MA-MADS genes.
Inaba
Akitsugu
A
Faculty of Agriculture, Okayama University, Tsushima, Okayama, 700-8530 Japan. ainaba@cc.okayama-u.ac.jp
Liu
Xuejun
X
Yokotani
Naoki
N
Yamane
Miki
M
Lu
Wang-Jin
WJ
Nakano
Ryohei
R
Kubo
Yasutaka
Y
D000598:Amino Acids, Cyclic / Q000378:metabolism; D003521:Cyclopropanes / Q000494:pharmacology; D005030:Ethylenes / Q000096:biosynthesis*; D005638:Fruit / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000502:physiology*; D008190:Lyases / Q000378:metabolism; D008969:Molecular Sequence Data; D028521:Musa / Q000187:drug effects / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D013997:Time Factors
D000598:Amino Acids, Cyclic; D003521:Cyclopropanes; D005030:Ethylenes; D010940:Plant Proteins; C023863:1-aminocyclopropane-1-carboxylic acid; C105498:1-methylcyclopropane; C036216:ethylene; D008190:Lyases; C021773:1-aminocyclopropanecarboxylate synthase