A HISTIDINE DECARBOXYLASE-LIKE MESSENGER-RNA IS INVOLVED IN TOMATO FRUIT RIPENING

DNA sequencing of a tomato ripening-related cDNA, TOM 92, revealed an open reading frame with homology to several pyridoxal 5'-phosphate his tidine decarboxylases, containing the conserved amino acid residues kn own to bind pyridoxal phosphate and alpha-fluoromethylhistidine, an in hibitor of enzyme activity. TOM 92 mRNA accumulated during early fruit ripening and then declined. Fruit of the ripening-impaired tomato mut ant, ripening inhibitor (rin), did not accumulate TOM 92 mRNA, and its accumulation was not restored by treatment of fruit with ethylene. Th e TOM 92 mRNA was not detected in tomato leaves and unripe fruit.