Most transport proteins in plant cells are energized by electrochemical gradients of protons across the plasma membrane. The formation of these gradients is due to the action of plasma membrane H+ pumps fuelled by ATP. The plasma membrane H+-ATPases share a membrane topography and general mechanism of action with other P-type ATPases, but differ in regulatory properties. Recent advances in the field include the identification of the complete H+-ATPase gene family in Arabidopsis, analysis of H+-ATPase function by the methods of reverse genetics, an improved understanding of the posttranslational regulation of pump activity by 14-3-3 proteins, novel insights into the H+ transport mechanism, and progress in structural biology. Furthermore, the elucidation of the three-dimensional structure of a related Ca2+ pump has implications for understanding of structure-function relationships for the plant plasma membrane H+-ATPase.

PLANT PLASMA MEMBRANE H+-ATPases: Powerhouses for Nutrient Uptake.

https://febs.onlinelibrary.wiley.com/doi/pdf/10.1016/S0014-5793%2801%2903288-4

How do 14-3-3 proteins work? – Gatekeeper phosphorylation and the molecular anvil hypothesis

Large-scale Analysis of in Vivo Phosphorylated Membrane Proteins by Immobilized Metal Ion Affinity Chromatography and Mass Spectrometry

P-type ATPases are ion pumps that carry out many fundamental processes in biology and medicine, ranging from the generation of membrane potential to muscle contraction and the removal of toxic ions from cells. Making use of the energy stored in ATP, they transport specific ions across the cell membrane against a concentration gradient. Recent X-ray structures and homology models of P-type pumps now provide a basis for understanding the molecular mechanism of ATP-driven ion transport.

Biology, structure and mechanism of P-type ATPases

P-type ATPases form a large superfamily of cation and lipid pumps. They are remarkably simple with only a single catalytic subunit and carry out large domain motions during transport. The atomic structure of P-type ATPases in different conformations, together with ample mutagenesis evidence, has provided detailed insights into the pumping mechanism by these biological nanomachines. Phylogenetically, P-type ATPases are divided into five subfamilies, P1–P5. These subfamilies differ with respect to transported ligands and the way they are regulated.

P-Type ATPases

Binding of 14-3-3 protein to the plasma membrane H+-ATPase AHA2 involves the three C-terminal residues tyr946-Thr-Val and requires phosphorylation of Thr947

Katrine Drumm

Papers

Binding of 14-3-3 protein to the plasma membrane H+-ATPase AHA2 involves the three C-terminal residues tyr946-Thr-Val and requires phosphorylation of Thr947