Analysis of two L-Galactono-1,4-lactone-responsive genes with complementary expression during the development of Arabidopsis thaliana.
Unraveling the role of genes annotated as protein of unknown function is of importance in progression of plant science. l-Galactono-1,4-lactone (l-GalL) is the terminal precursor for ascorbic acid (AsA) biosynthesis in Arabidopsis thaliana, and a previous study showed two DUF (domains of unknown function) 642 family genes (At1g80240 and At5g25460, designated as DGR1 and DGR2, respectively) to be sensitive to it. In this work, leaves from wild-type Arabidopsis were fed with d-glucose, l-galactose, l-GalL and AsA, and the expression level of the At1g80240 and At5g25460 genes showed a specific response to l-GalL, but not to the other supplements despite the increases of the tissue AsA contents. Analysis of promoter-β-glucuronidase (GUS) transgenic plants showed the two genes to be complementarily expressed at the root apex and in the rest of the root excluding the apex, respectively, in both young and old seedlings, and to be expressed at the leaf primordia. The GUS activity under the control of the At5g25460 promoter was high in the cotyledon and leaf veins of young seedlings. These findings were consistent with the results of quantitative real-time PCR. Interestingly, the T-DNA insertion mutant of At5g25460 (SALK_125079) displayed shorter roots and smaller rosettes than Col-0; however, no phenotypic difference was observed between the T-DNA insertion mutant of At1g80240 and the wild type. This is the first report on the expression and functional analysis of these two DUF642 family genes, with the results revealing the contribution of DGR genes to the development of Arabidopsis.
Department of Applied Bioscience and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504 Japan.
Yongshun
Y
Gao
Adebanjo A
AA
Badejo
Yoshihiro
Y
Sawa
Takahiro
T
Ishikawa
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D001205:Ascorbic Acid / Q000494:pharmacology; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D005690:Galactose / Q000378:metabolism; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D017343:Genes, Plant / Q000235:genetics*; D005966:Glucuronidase / Q000378:metabolism; D007783:Lactones / Q000494:pharmacology*; D008969:Molecular Sequence Data; D005810:Multigene Family; D009154:Mutation / Q000235:genetics; D010641:Phenotype; D010802:Phylogeny; D018515:Plant Leaves / Q000187:drug effects / Q000235:genetics / Q000254:growth & development; D018517:Plant Roots / Q000187:drug effects / Q000235:genetics / Q000254:growth & development; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding / Q000187:drug effects; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D013400:Sugar Acids / Q000494:pharmacology*
D029681:Arabidopsis Proteins; D002352:Carrier Proteins; C575337:DGR1 protein, Arabidopsis; C575338:DGR2 protein, Arabidopsis; D007783:Lactones; D012333:RNA, Messenger; D011994:Recombinant Proteins; D013400:Sugar Acids; C534014:galactono-1,4-lactone; D005966:Glucuronidase; D001205:Ascorbic Acid; D005690:Galactose