Role of the 14-3-3 C-terminal region in the interaction with the plasma membrane H+-ATPase.
The 14-3-3 proteins are a family of proteins present in a number of isoforms in all eukaryotes and involved in the control of many cellular functions. Regulation of different activities is achieved by binding to phosphorylated targets through a conserved mechanism. Although in many systems isoform specificity has been demonstrated, the underlying molecular basis is still unclear. The sequences of 14-3-3 isoforms are highly conserved, divergence occurring at the N- and C-terminal regions. Recently it has been suggested that the C-terminal domain of 14-3-3 may regulate protein binding to the targets. Here we study the role of the C-terminal region of maize isoform GF14-6 in the interaction with the plant plasma membrane H(+)-ATPase. Results obtained demonstrate that removal of the last 22 amino acids residues of GF14-6 increases binding to H(+)-ATPase and stimulation of its activity. C-terminal deletion, moreover, reduces 14-3-3 sensitivity to cations. We also show that a peptide reproducing the GF14-6 C-terminus is able to bind to the C-terminal domain of H(+)-ATPase and to stimulate the enzyme activity. The implications of these findings for a integrated model of 14-3-3 interaction with H(+)-ATPase are discussed.
Visconti
Sabina
S
Department of Biology, University of Rome Tor Vergata, via della Ricerca Scientifica, 00133, Rome, Italy.
Camoni
Lorenzo
L
Marra
Mauro
M
Aducci
Patrizia
P
D048948:14-3-3 Proteins / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D054730:Protein Interaction Domains and Motifs; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D006180:Proton-Translocating ATPases / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment; D017384:Sequence Deletion; D003313:Zea mays / Q000235:genetics* / Q000378:metabolism
D048948:14-3-3 Proteins; D004268:DNA-Binding Proteins; C091848:GRF1 protein, Zea mays; D010940:Plant Proteins; D020033:Protein Isoforms; D006180:Proton-Translocating ATPases