Tomato FRUITFULL homologs regulate fruit ripening via ethylene biosynthesis.

Certain MADS-box transcription factors play central roles in regulating fruit ripening. RIPENING INHIBITOR (RIN), a tomato MADS-domain protein, acts as a global regulator of ripening, affecting the climacteric rise of ethylene, pigmentation changes, and fruit softening. Previously, we showed that two MADS-domain proteins, the FRUITFULL homologs FUL1 and FUL2, form complexes with RIN.

Transcriptional regulation of fruit ripening by tomato FRUITFULL homologs and associated MADS box proteins.

The tomato (Solanum lycopersicum) MADS box FRUITFULL homologs FUL1 and FUL2 act as key ripening regulators and interact with the master regulator MADS box protein RIPENING INHIBITOR (RIN). Here, we report the large-scale identification of direct targets of FUL1 and FUL2 by transcriptome analysis of FUL1/FUL2 suppressed fruits and chromatin immunoprecipitation coupled with microarray analysis (ChIP-chip) targeting tomato gene promoters. The ChIP-chip and transcriptome analysis identified FUL1/FUL2 target genes that contain at least one genomic region bound by FUL1 or FUL2 (regions that occur mainly in their promoters) and exhibit FUL1/FUL2-dependent expression during ripening.

[Examination of processed vegetable foods for the presence of common DNA sequences of genetically modified tomatoes].

The contamination of processed vegetable foods with genetically modified tomatoes was investigated by the use of qualitative PCR methods to detect the cauliflower mosaic virus 35S promoter (P35S) and the kanamycin resistance gene (NPTII). DNA fragments of P35S and NPTII were detected in vegetable juice samples, possibly due to contamination with the genomes of cauliflower mosaic virus infecting juice ingredients of Brassica species and soil bacteria, respectively. Therefore, to detect the transformation construct sequences of GM tomatoes, primer pairs were designed for qualitative PCR to specifically detect the border region between P35S and NPTII, and the border region between nopaline synthase gene promoter and NPTII.

Inhibition of CUTIN DEFICIENT 2 Causes Defects in Cuticle Function and Structure and Metabolite Changes in Tomato Fruit.

Tomato (Solanum lycopersicum) fruit cuticle has been extensively studied due to its effect on the biochemical and physiological properties of the fruit. To date, several tomato mutants defective in proper cuticle formation have been identified. To gain insight into tomato cuticle formation, we investigated one such mutant, sticky peel/light green (pe lg).

Tomato FRUITFULL homologues act in fruit ripening via forming MADS-box transcription factor complexes with RIN.

The tomato MADS-box transcription factor RIN acts as a master regulator of fruit ripening. Here, we identified MADS-box proteins that interact with RIN; we also provide evidence that these proteins act in the regulation of fruit ripening. We conducted a yeast two-hybrid screen of a cDNA library from ripening fruit, for genes encoding proteins that bind to RIN.

MACROCALYX and JOINTLESS interact in the transcriptional regulation of tomato fruit abscission zone development.

Abscission in plants is a crucial process used to shed organs such as leaves, flowers, and fruits when they are senescent, damaged, or mature. Abscission occurs at predetermined positions called abscission zones (AZs). Although the regulation of fruit abscission is essential for agriculture, the developmental mechanisms remain unclear.

DNA-binding specificity, transcriptional activation potential, and the rin mutation effect for the tomato fruit-ripening regulator RIN.

The RIN gene encodes a putative MADS box transcription factor that controls tomato fruit ripening, and its ripening inhibitor (rin) mutation yields non-ripening fruit. In this study, the molecular properties of RIN and the rin mutant protein were clarified. The results revealed that the RIN protein accumulates in ripening fruit specifically and is localized in the nucleus of the cell.

Ethylene biosynthesis regulation in tomato fruit from the F1 hybrid of the ripening inhibitor (rin) mutant.

We have previously shown a significant decrease in the ethylene production in tomato fruit from the RIN/rin genotype. In this present study, we evaluated the amount of 1-aminocyclopropane-1-carboxylic acid (ACC) and the gene expression and enzymatic activities of ACC synthase (ACS) and ACC oxidase (ACO) to find which type of regulation influenced this low ethylene production. The results suggest that the decreased ethylene production was due to transcriptional regulation of the ACS and ACO genes by the heterozygous effect of the rin gene.

Reduction of allergenic proteins by the effect of the ripening inhibitor (rin) mutant gene in an F1 hybrid of the rin mutant tomato.

The ripening inhibitor (rin) mutant tomato yields non-ripening fruit, and the rin hybrid fruit (RIN/rin) shows an intermediate phenotype between the wild and mutant fruit, that is, red-ripe and extended shelf life. We found by a microarray analysis that the genes encoding possible allergenic proteins were expressed at a significantly lower level in the rin hybrid fruit than in the wild-type fruit. These allergenic proteins, which were beta-fructofuranosidase and polygalacturonase 2A (PG-2A), were confirmed to accumulate at a lower level in the rin hybrid fruit than in the wild-type fruit.

A role for arabinogalactan proteins in gibberellin-induced alpha-amylase production in barley aleurone cells.

Arabinogalactan proteins (AGPs) are plant proteoglycans that have been implicated in plant growth and development. The possible involvement of AGPs in the action of gibberellin (GA), a class of plant hormones, was examined by applying beta-glucosyl Yariv reagent (beta-Glc)3Y, a synthetic phenyl glycoside that interacts selectively with AGPs, to barley aleurone protoplasts. Gibberellin induces transcription and secretion of alpha-amylases in the protoplasts.