Convergent evolution of shoots in land plants: lack of auxin polar transport in moss shoots
Convergent evolution of shoots in land plants: lack of auxin polar transport in moss shoots
复制标题
DOI：
10.1111/j.1525-142x.2008.00225.x
复制
发表时间：
2008-03-01
影响因子：
2.9
通讯作者：
Hasebe, Mitsuyasu
中科院分区：
文献类型：
--
作者：
Fujita, Tomomichi;Sakaguchi, Hisako;Hasebe, Mitsuyasu
茎是由茎和叶组成的重复结构，是陆生植物的基本形体。维管植物在二倍体一代形成茎，而非维管植物如苔藓在单倍体一代形成茎。目前尚不清楚是否所有陆地植物在芽发育过程中都使用类似的分子机制，也不清楚芽发育的遗传网络是如何进化的。生长素分布的控制，特别是通过极性运输对开花植物芽部发育起着至关重要的作用。我们没有检测到生长素在几种苔藓的配子体芽中的极性运输，但在没有芽结构的苔藓的孢子体中检测到它。生长素运输抑制剂处理导致胚胎发育异常，与开花植物一样，但没有引起单倍体芽的任何形态变化。我们将大豆生长素诱导启动子GH3与GUS报告基因融合，并利用它间接检测了生长素在苔藓小壶菌中的分布。生长素运输抑制剂NPA没有引起单倍体茎部生长素分布的任何变化。这些结果表明，生长素的极性转运不参与苔藓单倍体芽的发育，维管植物和苔藓的芽在发育过程中很可能受到不同的调控。
The shoot is a repeated structure made up of stems and leaves and is the basic body plan in land plants. Vascular plants form a shoot in the diploid generation, whereas nonvascular plants such as mosses form a shoot in the haploid generation. It is not clear whether all land plants use similar molecular mechanisms in shoot development or how the genetic networks for shoot development evolved. The control of auxin distribution, especially by polar auxin transport, is essential for shoot development in flowering plants. We did not detect polar auxin transport in the gametophytic shoots of several mosses, but did detect it in the sporophytes of mosses without shoot structure. Treatment with auxin transport inhibitors resulted in abnormal embryo development, as in flowering plants, but did not cause any morphological changes in the haploid shoots. We fused the soybean auxin-inducible promoter GH3 with a GUS reporter gene and used it to indirectly detect auxin distribution in the moss Physcomitrella patens. An auxin transport inhibitor NPA did not cause any changes in the putative distribution of auxin in the haploid shoot. These results indicate that polar auxin transport is not involved in haploid shoot development in mosses and that shoots in vascular plants and mosses are most likely regulated differently during development.