title: Function and regulation of the two major plant plasma membrane H+-ATPases.
abstract: Plant plasma membrane H(+)-ATPases are encoded by a family of about ten genes organized into five subfamilies. Subfamilies I and II contain the most widely and highly expressed genes. In Nicotiana plumbaginifolia, they are represented, respectively, by pma2 (plasma membrane H(+)-ATPase) and pma4. When expressed in the yeast Saccharomyces cerevisiae, the two isoforms show different kinetics and are differently regulated by phosphorylation of the penultimate threonine residue and binding of regulatory 14-3-3 proteins. To determine if these differences also occurred in plant tissues, we developed an experimental approach allowing the characterization of a single isoform in the plant. When PMA2 bearing a 6-His tag was expressed under a strong transcription promoter in Nicotiana tabacum BY2 cells, solubilized from microsomal membranes and purified, the penultimate threonine was found to be phosphorylated, thus validating the model.
authors.affiliation: Unité de Biochimie physiologique, Institut des Sciences de la Vie, Université catholique de Louvain, Croix du Sud, Belgium.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Woloszynska
authors.forename: Justyna
authors.initials: J
authors.lastname: Kanczewska
authors.forename: Artem
authors.initials: A
authors.lastname: Drabkin
authors.forename: Olivier
authors.initials: O
authors.lastname: Maudoux
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Dambly
authors.forename: Marc
authors.initials: M
authors.lastname: Boutry
mesh_terms: D000595:Amino Acid Sequence; D002462:Cell Membrane / Q000201:enzymology*; D003001:Cloning, Molecular; D015971:Gene Expression Regulation, Enzymologic; D007527:Isoenzymes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D007700:Kinetics; D008958:Models, Molecular; D017433:Protein Structure, Secondary; D006180:Proton-Translocating ATPases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology; D014026:Nicotiana / Q000201:enzymology*
chemical_list: D007527:Isoenzymes; D011994:Recombinant Proteins; D006180:Proton-Translocating ATPases