OsLBD3-7基因过表达导致水稻叶片近轴卷曲

发布时间：2018-02-07 13:13

本文关键词： 水稻叶片卷曲 LBD基因家族泡状细胞　出处：《中国农业科学院》2016年硕士论文　论文类型：学位论文

【摘要】：水稻叶片是光合作用、呼吸作用、蒸腾作用的重要场所,是决定水稻产量的重要农艺性状之一。叶片适度卷曲有利于叶片挺直,改善披垂状态,增加光合作用和水稻单产。泡状细胞是与卷叶性状相关的位于叶片近轴面的薄壁细胞,当植物处于干旱环境时,泡状细胞失水,导致叶片近轴卷曲。本研究发现了一个新LBD家族基因OsLBD3-7可以通过调节泡状细胞,影响叶片卷曲。LBD基因家族是植物特异的一类转录因子,含有一个由与DNA元件相互作用的半胱氨酸保守结构域、GAS保守结构域和与蛋白质相互作用的羧基端亮氨酸保守结构构成的LOB保守结构域,参与侧生器官原基的启动和形态建成,对植物特定器官的形成与发育具有重要影响。研究发现:OsLBD3-7融合VP64形成的人工合成转录因子OsLBD3-7V和OsLBD3-7的简单过表达转基因植株均呈现剑叶宽度减少和近轴卷曲表型;叶片横截面细胞学切片分析表明,泡状细胞数目和面积减少导致叶片近轴卷曲。利用定量PCR检测了OsLBD3-7表达谱,发现该基因在所有组织器官中都有表达,尤其在根和鞘组织中表达量较高;亚细胞定位结果表明定位于细胞核中和细胞膜上。酵母自激活活性结果表明OsLBD3-7为弱转录激活子。进一步在OsLBD3-7V和OsLBD3-7转基因植物中对泡状细胞调节基因检测结果显示,泡状细胞负调节基因表达量升高,而正调节基因表达量降低,表明OsLBD3-7作为泡状细胞上游负调节子参与叶片卷叶调控。
[Abstract]:Rice leaf is an important place for photosynthesis, respiration and transpiration, which is one of the important agronomic traits that determine rice yield. Increased photosynthesis and rice yield. Vesicular cells are paraxial parenchyma cells associated with leaf curl traits. When plants are in dry conditions, bubbly cells lose water. In this study, we found that a new LBD family gene OsLBD3-7 can affect leaf curl. LBD gene family is a kind of plant specific transcription factors by regulating vesicular cells. A conserved LOB domain consisting of a cysteine conserved domain interacting with DNA elements and a carboxyl-terminal leucine conserved domain interacting with proteins is involved in the initiation and morphogenesis of the primordium of the lateral organ. It was found that the simple overexpression of OsLBD3-7V and OsLBD3-7, a synthetic transcription factor formed by the fusion of VP64, showed a reduced leaf width and a coiled phenotype in the near axis of the transgenic plants, which had a significant effect on the formation and development of specific organs in plants. The cytological analysis of leaf cross-section showed that the decrease of the number and area of vesicular cells resulted in leaf coiling. The expression profile of OsLBD3-7 was detected by quantitative PCR, and it was found that the gene was expressed in all tissues and organs. Especially in the root and sheath tissue, the expression level was higher. The results of subcellular localization showed that it was located in the nucleus and the cell membrane. The self-activation activity of yeast indicated that OsLBD3-7 was a weak transcriptional activator. Furthermore, in OsLBD3-7V and OsLBD3-7 transgenic plants, the regulatory genes of vesicular cells were detected. The expression of negative regulatory genes increased in vesicular cells, but decreased in positive ones, indicating that OsLBD3-7, as a negative regulator upstream of bubbly cells, was involved in leaf coiling regulation.
【学位授予单位】：中国农业科学院
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：S511

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