A novel mechanism of P-type ATPase autoinhibition involving both termini of the protein.
The activity of many P-type ATPases is found to be regulated by interacting proteins or autoinhibitory elements located in N- or C-terminal extensions. An extended C terminus of fungal and plant P-type plasma membrane H(+)-ATPases has long been recognized to be part of a regulatory apparatus involving an autoinhibitory domain. Here we demonstrate that both the N and the C termini of the plant plasma membrane H(+)-ATPase are directly involved in controlling the pump activity state and that N-terminal displacements are coupled to secondary modifications taking place at the C-terminal end. This identifies the first group of P-type ATPases for which both ends of the polypeptide chain constitute regulatory domains, which together contribute to the autoinhibitory apparatus. This suggests an intricate mechanism of cis-regulation with both termini of the protein communicating to obtain the necessary control of the enzyme activity state.
Ekberg
Kira
K
Plant Physiology and Anatomy Laboratory, Department of Plant Biology and Biotechnology, University of Copenhagen, Danish National Research Foundation, Frederiksberg, Denmark.
Palmgren
Michael G
MG
Veierskov
Bjarke
B
Buch-Pedersen
Morten J
MJ
D048948:14-3-3 Proteins / Q000235:genetics / Q000378:metabolism; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000166:cytology / Q000201:enzymology*; D029681:Arabidopsis Proteins / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D025222:Chloroplast Proton-Translocating ATPases / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004789:Enzyme Activation; D008969:Molecular Sequence Data; D016296:Mutagenesis; D017434:Protein Structure, Tertiary
D048948:14-3-3 Proteins; D029681:Arabidopsis Proteins; D025222:Chloroplast Proton-Translocating ATPases