Molecular and cellular characterizations of a cDNA clone encoding a novel isozyme of aldehyde dehydrogenase from rice.
Aldehyde dehydrogenases (ALDHs) are a group of enzymes catalyzing the conversion of aldehydes to the corresponding acids. In mammals and yeasts, at least two isozymes of ALDH are known to be involved in ethanol metabolism (cytosolic ALDH1 and mitochondrial ALDH2). Although mitochondrial ALDH isozymes have previously been identified in several plants, such as maize and tobacco, it is unclear whether cytosolic ALDH isozymes also exist in plants. In this study, we identified and characterized a cDNA clone encoding aldehyde dehydrogenase (ALDH1a) from rice (Oryza sativa L. cv. Nipponbare). The open reading frame of this clone did not contain a typical mitochondrial targeting signal. Analysis of the subcellular localization of ALDH1a using green fluorescent protein (GFP) suggested that ALDH1a is a cytosolic enzyme rather than a mitochondrial enzyme. A genomic Southern hybridization indicated that sequences homologous to the ALDH1a gene are present in at least two regions of the rice genome. Amplification by RT-PCR showed that ALDH1a is expressed strongly in roots, but not in leaves, of rice seedlings, suggesting that ALDH1a functions in roots.
Li
Y
Y
Laboratory of Plant Molecular Genetics, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Japan.
Nakazono
M
M
Tsutsumi
N
N
Hirai
A
A
D000444:Aldehyde Dehydrogenase / Q000235:genetics*; D000595:Amino Acid Sequence; D001483:Base Sequence; D015139:Blotting, Southern; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics*; D018744:DNA, Plant / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D049452:Green Fluorescent Proteins; D007527:Isoenzymes / Q000235:genetics; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D012275:Oryza / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D010802:Phylogeny; D010947:Plants, Toxic; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution; D014026:Nicotiana / Q000166:cytology / Q000235:genetics
D018076:DNA, Complementary; D018744:DNA, Plant; D007527:Isoenzymes; D008164:Luminescent Proteins; D018749:RNA, Plant; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins; D000444:Aldehyde Dehydrogenase