Thomine S, Lelièvre F, Boufflet M, Guern J, Barbier-Brygoo H
Institut des Sciences Végétales, Centre National de la Recherche Scientifique, Gif-sur-Yvette, France.
Plant Physiol. 1997 Oct;115(2):533-42. doi: 10.1104/pp.115.2.533.
Anion channels are thought to participate in signal transduction and turgor regulation in higher plant cells. The regulation of hypocotyl cell elongation is a situation in which these channels could play important roles because it involves ionic fluxes that are implicated in turgor control and orchestrated by various signals. We have used a pharmacological approach to reveal the contribution of anion channels in the regulation of the development of hypocotyls by auxins. Auxins induce an inhibition of elongation, a disintegration of the cortical cell layers, and the formation of adventitious roots on Arabidopsis thaliana hypocotyls grown in the dark. Anion-channel blockers such as anthracene-9-carboxylic acid, 4,4'-diisothiocyanatostilbene-2-2'-disulfonic acid, 4-acetamido-4'-isothiocyanato-stilbene-2-2'-disulfonic acid, and R(+)-methylindazone; indanyloxyacteic acid-94, which produce little or no stimulation of hypocotyl elongation by themselves, are able to counteract the inhibition and the disintegration induced by auxins with various efficiencies. This interference appears to be specific for auxins and does not occur when hypocotyl elongation is inhibited by other growth regulators such as ethylene or cytokinins. The putative involvement of anion channels in auxin signal transduction is discussed.
阴离子通道被认为参与高等植物细胞中的信号转导和膨压调节。下胚轴细胞伸长的调节是这些通道可能发挥重要作用的一种情况，因为它涉及与膨压控制相关且由各种信号协调的离子通量。我们采用药理学方法来揭示阴离子通道在生长素对下胚轴发育调节中的作用。生长素会抑制黑暗中生长的拟南芥下胚轴的伸长、导致皮层细胞层解体并促进不定根的形成。阴离子通道阻滞剂，如蒽-9-羧酸、4,4'-二异硫氰酸根合芪-2,2'-二磺酸、4-乙酰氨基-4'-异硫氰酸根合芪-2,2'-二磺酸和R(+)-甲基吲唑酮；茚满氧基乙酸-94，它们自身对下胚轴伸长几乎没有或没有刺激作用，但能够以不同效率抵消生长素诱导的抑制和解体作用。这种干扰似乎对生长素具有特异性，当用乙烯或细胞分裂素等其他生长调节剂抑制下胚轴伸长时不会发生。本文讨论了阴离子通道在生长素信号转导中的可能作用。
