Molecular cloning and characterization of a novel 1-aminocyclopropane-1-carboxylate oxidase gene involved in ripening of banana fruits.
One novel banana fruit ripening related 1-aminocyclopropane-1-carboxylate (ACC) oxidase gene quite different from ACC oxidase genes from other species was cloned. In contrast to other studies, the polypeptide encoded by this gene, named Mh-ACO1, lacks the putative leucine zipper motif which is conserved in all known ACC oxidases including the other previously reported banana ACC oxidase, Mh-ACO2. The locus consists of two nearly identical paralogous ACC oxidase genes arranged in opposite orientation and separated by a 3.1-kb intergenic region. The has only two introns, at positions identical to , which comprises a coding region interrupted by three introns. The predicted amino acid sequence of Mh-ACO1 shares less than 50% identity to those of ACC oxidase from other climacteric fruits, while that of Mh-ACO2 shows more than 65% homology. When expressed in Saccharomyces cerevisiae -encoded protein possessed the enzyme activity for ethylene conversion. The levels of mRNA corresponding to both and increased during fruit ripening and were induced by exogenous ethylene. We conclude that both and contribute to increased ethylene production in fruits and these two genes are differentially expressed in fruits and other organs in banana.
Do
Yi-Yin
YY
Department of Horticulture, National Taiwan University, No. 1, Roosevelt Road, Section 4, Taipei 10617, Taiwan, Republic of China.
Thay
Te-Shih
TS
Chang
Tang-Wei
TW
Huang
Pung-Ling
PL
D000594:Amino Acid Oxidoreductases / Q000737:chemistry / Q000235:genetics*; D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D005638:Fruit / Q000201:enzymology / Q000254:growth & development*; D015870:Gene Expression; D015971:Gene Expression Regulation, Enzymologic; D008969:Molecular Sequence Data; D028521:Musa / Q000201:enzymology / Q000254:growth & development*; D011994:Recombinant Proteins; D012441:Saccharomyces cerevisiae / Q000235:genetics; D014162:Transfection
D011994:Recombinant Proteins; D000594:Amino Acid Oxidoreductases; C059460:1-aminocyclopropane-1-carboxylic acid oxidase