Genetic approaches to auxin action.
Genetic approaches to auxin action.
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DOI：
10.1111/j.1365-3040.1994.tb00147.x
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发表时间：
1994-05
期刊：
影响因子：
--
通讯作者：
L. Hobbie;M. Estelle
中科院分区：
文献类型：
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作者：
L. Hobbie;M. Estelle
关于生长素作用的分子机制和生长素在植物生长发育中的确切功能等长期存在的问题，正开始通过对突变体和转基因植物的研究而得到解答。本文综述了近年来维管植物在这方面的研究进展。从这些研究中可以得出一些结论。首先，生长素似乎对细胞分裂和活力至关重要，因为从组织培养中分离出的生长素促生长素依赖于生长素生长，即使在外源供应生长素的情况下也不能再生成植物。其次，带有改变生长素水平的转基因植物能够通过合成和接合来调节细胞的生长素浓度；野生型植物可能也有这种调节能力。第三，生长素水平改变的转基因植株和对生长素敏感性改变的突变植株的表型证实了早期的生理学研究，即生长素在调节根尖优势、根和维管组织的发育以及向地性反应中发挥作用。最后，一个突变鉴定的生长素作用重要基因的克隆，以及积累的生化证据，暗示了在生长素反应途径中蛋白质降解的主要作用。
Answers to long-standing questions concerning the molecular mechanism of auxin action and auxin's exact functions in plant growth and development are beginning to be uncovered through studies using mutant and transgenic plants. We review recent work in this area in vascular plants. A number of conclusions can be drawn from these studies. First, auxin appears essential for cell division and viability, as auxin auxotrophs isolated in tissue culture are dependent on auxin for growth and cannot be regenerated into plants even when auxin is supplied exogenously. Secondly, plants with transgenes that alter auxin levels are able to regulate cellular auxin concentrations by synthesis and conjugation; wild-type plants are probably also capable of such regulation. Thirdly, the phenotypes of transgenic plants with altered auxin levels and of mutant plants with altered sensitivity to auxin confirm earlier physiological studies which indicated a role for auxin in regulation of apical dominance, in development of roots and vascular tissue, and in the gravitropic response. Finally, the cloning of a mutationally identified gene important for auxin action, along with accumulating biochemical evidence, hints at a major role for protein degradation in the auxin response pathway.