Laboratory of Plant Gene Expression, Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Japan.
Plant Signal Behav. 2011 Sep;6(9):1405-7. doi: 10.4161/psb.6.9.16934.
Legumes can establish a symbiosis with rhizobia and form root nodules that function as an apparatus for nitrogen fixation. Nodule development is regulated by several phytohormones including auxin. Although accumulation of auxin is necessary to initiate the nodulation of indeterminate nodules, the functions of auxin on the nodulation of determinate nodules have been less characterized. In this study, the functions of auxin in nodule development in Lotus japonicus have been demonstrated using an auxin responsive promoter and auxin inhibitors. We found that the lenticel formation on the nodule surface was sensitive to the auxin defect. Further analysis indicated that failure in the development of the vascular bundle of the determinate nodule, which was regulated by auxin, was the cause of the disappearance of lenticels.
豆科植物可以与根瘤菌建立共生关系，并形成根瘤，作为固氮的装置。根瘤的发育受几种植物激素的调节，包括生长素。虽然生长素的积累对于不定根瘤的起始是必要的，但生长素对定根瘤的结瘤功能的特征描述较少。在这项研究中，我们使用生长素响应启动子和生长素抑制剂，证明了生长素在豌豆结瘤发育中的作用。我们发现，不定根瘤表面皮孔的形成对生长素缺陷敏感。进一步的分析表明，生长素调节的定根瘤维管束发育的失败是皮孔消失的原因。
