Indoleacetic acid pretreatment of tobacco plants in vivo increases the in vitro sensitivity to auxin of the plasma membrane H(+)-ATPase from leaves and modifies the polypeptide composition of the membrane.
The sensitivity to auxin of the H(+)-ATPase-mediated proton translocation was investigated in vitro using purified plasma membrane vesicles from tobacco leaves. In vivo pretreatment of tobacco plants with auxin promotes a 100-fold increase of the in vitro sensitivity to auxin. This effect is specific for biologically active auxins and is dose- and time-dependent. In addition, pretreatment with auxin induces the accumulation of several polypeptides in the plasma membrane. These polypeptides constitute the first set of hormone-responsive polypeptides evidenced in plant membranes.
Santoni
V
V
Lab. Biochimie et Physiologie Végétales, INRA/ENSA-M/CNRS UA 573, Montpellier, France.
Vansuyt
G
G
Rossignol
M
M
D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D007210:Indoleacetic Acids / Q000494:pharmacology*; D008565:Membrane Proteins / Q000378:metabolism*; D010455:Peptides / Q000378:metabolism; D010947:Plants, Toxic; D006180:Proton-Translocating ATPases / Q000378:metabolism*; D014026:Nicotiana / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure
D007210:Indoleacetic Acids; D008565:Membrane Proteins; D010455:Peptides; C030737:indoleacetic acid; D006180:Proton-Translocating ATPases