RRC ID 6081
Author Yokotani N, Nakano R, Imanishi S, Nagata M, Inaba A, Kubo Y.
Title Ripening-associated ethylene biosynthesis in tomato fruit is autocatalytically and developmentally regulated.
Journal J. Exp. Bot.
Abstract To investigate the regulatory mechanism(s) of ethylene biosynthesis in fruit, transgenic tomatoes with all known LeEIL genes suppressed were produced by RNA interference engineering. The transgenic tomato exhibited ethylene insensitivity phenotypes such as non-ripening and the lack of the triple response and petiole epinasty of seedlings even in the presence of exogenous ethylene. Transgenic fruit exhibited a low but consistent increase in ethylene production beyond 40 days after anthesis (DAA), with limited LeACS2 and LeACS4 expression. 1-Methylcyclopropene (1-MCP), a potent inhibitor of ethylene perception, failed to inhibit the limited increase in ethylene production and expression of the two 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (ACS) genes in the transgenic fruit. These results suggest that ripening-associated ethylene (system 2) in wild-type tomato fruit consists of two parts: a small part regulated by a developmental factor through the ethylene-independent expression of LeACS2 and LeACS4 and a large part regulated by an autocatalytic system due to the ethylene-dependent expression of the same genes. The results further suggest that basal ethylene (system 1) is less likely to be involved in the transition to system 2. Even if the effect of system 1 ethylene is eliminated, fruit can show a small increase in ethylene production due to unknown developmental factors. This increase would be enough for the stimulation of autocatalytic ethylene production, leading to fruit ripening.
Volume 60(12)
Pages 3433-42
Published 2009
DOI 10.1093/jxb/erp185
PII erp185
PMID 19605457
PMC PMC2724697
MeSH Ethylenes / biosynthesis* Fruit / genetics Fruit / growth & development Fruit / physiology Gene Expression Regulation, Developmental* Gene Expression Regulation, Plant Lyases / genetics Lyases / metabolism Lycopersicon esculentum / enzymology Lycopersicon esculentum / genetics Lycopersicon esculentum / growth & development Lycopersicon esculentum / physiology* Plant Proteins / genetics Plant Proteins / metabolism
IF 5.36
Times Cited 53
Tomato TOMJPF00004(Ailsa Craig)