title: cDNA sequence and expression of subunit E of the vacuolar H(+)-ATPase in the inducible Crassulacean acid metabolism plant Mesembryanthemum crystallinum.
abstract: A cDNA coding for subunit E of the vacuolar H(+)-ATPase was cloned from Mesembryanthemum crystallinum, a plant which switches from C3-photosynthesis to Crassulacean acid metabolism under saline growth conditions. Sequence homology between the three subunit E-polypeptides of different higher plant species varied between 77.6 and 73.3%; peptide length was between 226 and 230 amino acid residues, 43 of which are invariant in all seven subunit E-polypeptides known so far from animals, fungi and plants. The deduced relative molecular mass of subunit E in Mesembryanthemum crystallinum is 26162 Da. Subunit E is present both in C3- and CAM-plants. mRNA levels increased severalfold in leaves of CAM-induced plants. This was accompanied by a less pronounced increase in subunit E protein. Obviously, expression is stimulated under conditions of increased requirement for tonoplast H(+)-pumping activity.
authors.affiliation: Julius-von-Sachs-Institut für Biowissenschaften, Julius-Maximilians-Universität Würzburg, Germany. dietz@botanik.uni-wuerzburg.de
authors.forename: K J
authors.initials: KJ
authors.lastname: Dietz
authors.forename: B
authors.initials: B
authors.lastname: Arbinger
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002264:Carboxylic Acids / Q000378:metabolism*; D018076:DNA, Complementary / Q000737:chemistry*; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010788:Photosynthesis; D010944:Plants / Q000201:enzymology* / Q000235:genetics / Q000648:ultrastructure; D006180:Proton-Translocating ATPases / Q000737:chemistry / Q000235:genetics*; D017385:Sequence Homology; D014617:Vacuoles / Q000201:enzymology*
chemical_list: D002264:Carboxylic Acids; D018076:DNA, Complementary; D046911:Macromolecular Substances; D006180:Proton-Translocating ATPases