Two Comments on Auxin Transport: The Uptake/Efflux-Mechanism and the Problem of Adaptation

Abstract

A “simple” transport scheme of auxin accumulation in the cytoplasm and auxin “secretion” from each cell consists of two specific molecular transmembrane processes at the plasmalemma: (1) an accumulation of IAA into the cytoplasm driven by a pH gradient and by the electrical membrane potential, and (2) an efflux of IAA through polarly distributed exit carriers. Figure 1 illustrates the mechanism at a cell or at an outside-out plasma membrane vesicle. The exit carriers are inhibited non-competitively by phytotropins and TIBA [3].KeywordsAuxin TransportPolar TransportPlasma Membrane VesicleTransport SchemeEfflux CarrierThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.