DEVELOPMENTAL AND HORMONAL-REGULATION OF A TRIOSEPHOSPHATE ISOMERASE GENE IN PETUNIA COROLLAS

We used a petunia corolla cDNA library to isolate a developmentally re gulated cDNA clone, tpi1, encoding the glycolytic enzyme triosephospha te isomerase (TPI). The cDNA contains an open reading frame of 762 bas e pairs, encoding a polypeptide of 254 amino acid residues. The deduce d protein shows 84% identity with the cytosolic tpi gene product of ma ize. Expression of the tpi1 gene is developmentally regulated during f lower development and induced by gibberellic acid (GA(3)) in detached corollas. We found a correlation between tpi1 expression and respirati on during corolla development and following GA(3) treatment. We sugges t that the activation of general biochemical pathways such as glycolys is and respiration by GA is required for corolla development.