Flowering time control in ornamental gloxinia (Sinningia speciosa) by manipulation of miR159 expression
Flowering time control in ornamental gloxinia (Sinningia speciosa) by manipulation of miR159 expression
复制标题
通过调控 miR159 表达控制观赏大岩桐 (Sinningia spiosa) 的开花时间
DOI：
10.1093/aob/mct034
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发表时间：
2013-05-01
期刊：
影响因子：
4.2
通讯作者：
Zhu, Muyuan
中科院分区：
文献类型：
--
作者：
Li, Xiaoyan;Bian, Hongwu;Zhu, Muyuan
Gloxinia （Sinningia speciosa）是一种很受欢迎的商业植物，因为它的花很吸引人，颜色很鲜艳。然而，在开花时间调控的遗传机制在很大程度上是未知的。最近对模式植物的研究表明，miR159在短日照期的花过渡中起负调控作用。本研究的目的是探讨基因修饰miR159的表达是否可以为gloxinia开花特性的调控提供有效的途径。通过农杆菌介导的高效转化体系，构建了过表达或抑制miR159的绿球菊转基因植株，研究了miR159对开花时间的影响。此外，还克隆了gloxinia GAMYB的全长cDNA (SsGAMYB)，并通过修饰RNA连接酶介导的cDNA末端快速扩增验证了其为miR159的靶点。过表达或抑制miR159的转基因植物分别表现出明显的开花晚或开花早。在花发育过程中，miR159与SsGAMYB的表达水平呈负相关。mir159介导的SsGAMYB表达影响SsLEAFY （SsLFY）和3个MADS-box基因（SsAP1、SsAP3和SsAG）的表达水平，这些基因调控GAMYB下游的花过渡。此外，miR159的抑制在一些转基因植物中引起花瓣和萼片的转化。mir159调控GAMYB的表达是花期调控的有效途径。miR159的转基因操作可以作为一种适用的策略来调节商业观赏植物的开花时间。
Gloxinia (Sinningia speciosa) is a popular commercial plant for its attractive and colourful flowers. However, the genetic mechanism of flowering time regulation in gloxinia is largely unknown. Recent studies on model plants have elucidated that miR159 acts as a negative regulator of floral transition in short-day photoperiods. The aim of this study was to investigate whether genetic modification of miR159 expression can offer an effective approach for regulation of flowering characteristics in gloxinia.Transgenic gloxinia plants were generated that over-express or suppress miR159 by means an efficient Agrobacterium-mediated transformation system in order to study the effect of miR159 on flowering time. In addition, the full-length cDNA of gloxinia GAMYB (SsGAMYB) was also cloned, and was verified to be a target of miR159 by modified RNA ligase-mediated 5 rapid amplification of cDNA ends.Transgenic gloxinia plants that over-express or suppress miR159 exhibited significantly late or early flowering, respectively. During flower development, the expression level of miR159 was negatively correlated with SsGAMYB in gloxinia. MiR159-mediated SsGAMYB expression affected the expression levels of SsLEAFY (SsLFY) and three MADS-box genes (SsAP1, SsAP3 and SsAG), which regulated floral transition downstream of GAMYB. In addition, suppression of miR159 caused a conversion of petals and sepals in a few transgenic plants.miR159-regulated GAMYB expression is an effective pathway of flowering time control in gloxinia. Transgenic manipulation of miR159 can be used as an applicable strategy to regulate flowering time in commercial ornamental plants.