title: Novel ABA- and dehydration-inducible aldehyde dehydrogenase genes isolated from the resurrection plant Craterostigma plantagineum and Arabidopsis thaliana.
abstract: In order to identify genes that are critical for the ABA-dependent stress response in the resurrection plant Craterostigma plantagineum, a gene was isolated with homology to class 3 variable substrate aldehyde dehydrogenases (ALDH). The C. plantagineum gene Cp-ALDH constitutes a novel class of plant ALDHs. In a search for corresponding genes from Arabidopsis thaliana, Ath-ALDH3 and Ath-ALDH4 were isolated, showing 70% and 80% similarity to Cp-ALDH. Phylogenetically, the Cp- and Ath-ALDH3 and -ALDH4 proteins are closely related to aldehyde dehydrogenases from bacteria and mammalian species and are separated from known plant ALDHs and betaine-aldehyde dehydrogenases (BADH). Cp-ALDH transcript and polypeptide are up-regulated in vegetative tissues and callus in response to dehydration or ABA-treatment. Ath-ALDH3 expression was induced in response to dehydration and ABA treatment, while Ath-ALDH4 is constitutively expressed at a low level. Recombinant Cp-ALDH protein oxidizes nonanal, propionaldehyde and acetaldehyde, with Km values of 2.2 microm, 0.27 mm and 3.23 mm, respectively, in an NAD-dependent manner. Immunogold electron microscopy shows that Cp-ALDH is localized in plastids.
authors.affiliation: Institute of Botany, University of Bonn, Kirschallee 1, 53115 Bonn, Germany. hhkirch@uni-bonn.de
authors.forename: H H
authors.initials: HH
authors.lastname: Kirch
authors.forename: A
authors.initials: A
authors.lastname: Nair
authors.forename: D
authors.initials: D
authors.lastname: Bartels
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism*; D000444:Aldehyde Dehydrogenase / Q000737:chemistry / Q000235:genetics*; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics*; D001483:Base Sequence; D017931:DNA Primers; D004926:Escherichia coli / Q000235:genetics; D019684:Magnoliopsida / Q000201:enzymology / Q000235:genetics*; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid; D014867:Water / Q000378:metabolism*
chemical_list: D017931:DNA Primers; D014867:Water; D000040:Abscisic Acid; D000444:Aldehyde Dehydrogenase