Over-expression of OsPIN2 leads to increased tiller numbers, angle and shorter plant height through suppression of OsLAZY1
Over-expression of OsPIN2 leads to increased tiller numbers, angle and shorter plant height through suppression of OsLAZY1
复制标题
OsPIN2 的过度表达通过抑制 OsLAZY1 导致分蘖数量增加、角度增加和株高缩短
DOI：
10.1111/j.1467-7652.2011.00637.x
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发表时间：
2012-02-01
影响因子：
13.8
通讯作者：
Xu, Guohua
中科院分区：
文献类型：
--
作者：
Chen, Yingnan;Fan, Xiaorong;Xu, Guohua
作物结构参数，如分蘖数、角度和株高，是育种计划中考虑的重要农艺性状。长期以来，生长素在植物中的分布被认为可以改变植物的结构。水稻(Oryza sativa L.)基因组包含12个编码生长素外流转运蛋白的PIN基因，包括4个PIN1和1个PIN2基因。在这里，我们报道了通过转基因方法在水稻中过表达OsPIN2。与野生型(WT)相比，日本晴)株高较低，分蘖较多，分蘖角度较大。生长素报告基因DR5：：GUS的表达模式和生长素分布的定量分析表明，OsPIN2过表达增加了生长素从地上部到根部的运输，导致相对于WT，生长素在根部的非组织特异性积累。过表达OsPIN2促进了生长素从地上部到根的运输，但没有改变根中生长素的极性模式。转基因植株在根生长过程中对生长素运输抑制剂N-1-萘基邻苯二甲酸的敏感性低于WT。过表达OsPIN2的植株抑制了水稻向重力性相关基因OsLazy1的表达，但未改变水稻分蘖角度控制基因OsPIN1b和OsTAC1的表达。这些数据表明，OsPIN2与OsPIN1b和OsTAC1一起控制水稻新梢构型，具有明显的生长素依赖的调控途径。通过遗传转化改变OsPIN2的表达可直接用于水稻构型的改良。
Crop architecture parameters such as tiller number, angle and plant height are important agronomic traits that have been considered for breeding programmes. Auxin distribution within the plant has long been recognized to alter architecture. The rice (Oryza sativa L.) genome contains 12 putative PIN genes encoding auxin efflux transporters, including four PIN1 and one PIN2 genes. Here, we report that over-expression of OsPIN2 through a transgenic approach in rice (Japonica cv. Nipponbare) led to a shorter plant height, more tillers and a larger tiller angle when compared with wild type (WT). The expression patterns of the auxin reporter DR5::GUS and quantification of auxin distribution showed that OsPIN2 over-expression increased auxin transport from the shoot to the rootshoot junction, resulting in a non-tissue-specific accumulation of more free auxin at the rootshoot junction relative to WT. Over-expression of OsPIN2 enhanced auxin transport from shoots to roots, but did not alter the polar auxin pattern in the roots. Transgenic plants were less sensitive to N-1-naphthylphthalamic acid, an auxin transport inhibitor, than WT in their root growth. OsPIN2-over-expressing plants had suppressed the expression of a gravitropism-related gene OsLazy1 in the shoots, but unaltered expression of OsPIN1b and OsTAC1, which were reported as tiller angle controllers in rice. The data suggest that OsPIN2 has a distinct auxin-dependent regulation pathway together with OsPIN1b and OsTAC1 controlling rice shoot architecture. Altering OsPIN2 expression by genetic transformation can be directly used for modifying rice architecture.