Open AccessMolecular cloning and sequence of cDNA encoding the plasma membrane proton pump (H+-ATPase) of Arabidopsis thaliana.
Author(s) -
Jeffrey F. Harper,
Terry K. Surowy,
Michael R. Sussman
Publication year - 1989
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.86.4.1234
Subject(s) - arabidopsis thaliana , biochemistry , biology , peptide sequence , complementary dna , amino acid , transmembrane protein , atpase , nucleic acid sequence , proton pump , arabidopsis , transmembrane domain , enzyme , gene , mutant , receptor
In plants, the transport of solutes across the plasma membrane is driven by a proton pump (H+-ATPase) that produces an electric potential and pH gradient. We have isolated and sequenced a full-length cDNA clone that encodes this enzyme in Arabidopsis thaliana. The protein predicted from its nucleotide sequence encodes 959 amino acids and has a molecular mass of 104,207 Da. The plant protein shows structural features common to a family of cation-translocating ATPases found in the plasma membrane of prokaryotic and eukaryotic cells, with the greatest overall identity in amino acid sequence (36%) to the H+-ATPase observed in the plasma membrane of fungi. The structure predicted from a hydropathy plot contains at least eight transmembrane segments, with most of the protein (73%) extending into the cytoplasm and only 5% of the residues exposed on the external surface. Unique features of the plant enzyme include diverged sequences at the amino and carboxyl termini as well as greater hydrophilic character in three extracellular loops.