AUTHOR=Pedersen Christian N., Axelsen Kristian B., Harper Jeffrey F , Palmgren Michael G. TITLE=Evolution of Plant P-Type ATPases JOURNAL=Frontiers in Plant Science VOLUME=3 YEAR=2012 URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2012.00031 DOI=10.3389/fpls.2012.00031 ISSN=1664-462X ABSTRACT=

Five organisms having completely sequenced genomes and belonging to all major branches of green plants (Viridiplantae) were analyzed with respect to their content of P-type ATPases encoding genes. These were the chlorophytes Ostreococcus tauri and Chlamydomonas reinhardtii, and the streptophytes Physcomitrella patens (a non-vascular moss), Selaginella moellendorffii (a primitive vascular plant), and Arabidopsis thaliana (a model flowering plant). Each organism contained sequences for all five subfamilies of P-type ATPases. Whereas Na⁺ and H⁺ pumps seem to mutually exclude each other in flowering plants and animals, they co-exist in chlorophytes, which show representatives for two kinds of Na⁺ pumps (P2C and P2D ATPases) as well as a primitive H⁺-ATPase. Both Na⁺ and H⁺ pumps also co-exist in the moss P. patens, which has a P2D Na⁺-ATPase. In contrast to the primitive H⁺-ATPases in chlorophytes and P. patens, the H⁺-ATPases from vascular plants all have a large C-terminal regulatory domain as well as a conserved Arg in transmembrane segment 5 that is predicted to function as part of a backflow protection mechanism. Together these features are predicted to enable H⁺ pumps in vascular plants to create large electrochemical gradients that can be modulated in response to diverse physiological cues. The complete inventory of P-type ATPases in the major branches of Viridiplantae is an important starting point for elucidating the evolution in plants of these important pumps.