MONITORING THE EFFECT OF JASMONATES ON THE EXPRESSION OF RIPENING RELATED GENES IN TOMATO FRUIT DISKS BY CDNA MACROARRAY

Abstract

Jasmonates show numerous effects on plant growth and development. In recent years, it is well known that jasmonates are important as a mediator of wound-and stress-induced signal transduction and induce expression of a variety of genes involved in defensive response. And it also has been revealed that jasmonates play an important role in fruit ripening. To determine if jasmonates affect the expression of the genes involved in ripening, we screened 10,911 cDNA clones for jasmonates responsiveness by a cDNA macroarray procedure. Hybridization to the filters was achieved using α- 33 P-labeled single-strand DNAs synthesized from mRNAs obtained from methyl jasmonate (MeJA)-treated and untreated 35 days after full bloom (DAFB) tomato pericarp disks. Data analysis of the results from wild type and non-ripening (nor) mutant tomato defined that mRNA levels of 81 genes were changed by more than three fold elevation in response to MeJA in wild type tomato and the number of genes whose mRNA levels were also induced more than three fold by MeJA in nor mutant tomato was 21. Homology searches with the sequences of the 21 genes revealed that 7 genes displayed similarity with genes of unknown function and 2 genes showed no homology with sequences on database. The use of the array to study fruit response in different genetic background and different treatment will help us to understand the mechanism of fruit ripening.