Analysis of Function and Agricultural Application of Plant Aldehyde oxidase using Transgenic Plants

点击翻译按钮获取中文摘要

Aldehyde oxidase (AO) has been extensively investigated in animals and microorganisms. In plants, however, there was only a limited information on this enzyme. A great interest in this enzyme has been in its possible involvement in indole-3-acetic acid (IAA) and abscisic acid (ABA) biosynthesis. In the present study, we cloned four full-length AO cDNAs from Arabidopsis thaliana and investigate their physiological functions using transgenic plants with these genes. We also tried to develop these results to agricultural application.(1) Four different putative AO cDNA clones were obtained from A. thaliana. Their products were analyzed by using antibodies each specific to four AOs in A. thaliana.(2) The four AO cDNAs were introduced into yeast Pichia pastoris and the products were functionally expressed in the yeast cells. The result revealed that two AO genes encoded three AOs in A. thaliana seedlings and another AO gene produced a leaf AO. Biochemical studies using AOs expressed in yeast indicated that one of seedling AO might be involved in IAA biosynthesis and a leaf AO is a most possible candidate of an AO that catalyzes oxidation of abscisic aldehyde to form ABA.(3) The four AO cDNA clones were introduced into A. thaliana and some over expressed and suppressed lines were obtained for each DNA construct.(4) We also succeeded screening several knockout lines with these genes.