Kramer Eric M
Physics Department, Simon's Rock College, 84 Alford Road, Great Barrington, MA 01230, USA.
Trends Plant Sci. 2004 Dec;9(12):578-82. doi: 10.1016/j.tplants.2004.10.010.
There is mounting evidence that plant tissues specialized for auxin transport coincide with local maxima in the auxin concentration. This result is difficult to reconcile with the traditional model of auxin transport, which relies on high levels of auxin efflux carrier expression. Because transporting cells maintain high levels of auxin efflux, one naively expects a depletion of auxin relative to surrounding tissues. Here I use a computer model of auxin transport in a background of parenchyma cells to evaluate the possible roles of the PIN and AUX/LAX families of putative auxin carriers in auxin accumulation. I describe two effective accumulation strategies and review the evidence that these strategies are used by plants.
越来越多的证据表明，专门用于生长素运输的植物组织与生长素浓度的局部最大值相吻合。这一结果很难与传统的生长素运输模型相协调，传统模型依赖于高水平的生长素外排载体表达。由于运输细胞维持高水平的生长素外排，人们天真地预期相对于周围组织生长素会减少。在这里，我使用一个在薄壁细胞背景下的生长素运输计算机模型，来评估假定的生长素载体PIN和AUX/LAX家族在生长素积累中的可能作用。我描述了两种有效的积累策略，并回顾了植物使用这些策略的证据。
