新疆固沙先锋植物羽毛针禾糖转运蛋白SWEET参与沙套发育的机制研究

羽毛针禾是重要的沙漠先锋植物，根具沙套，能保护根系、增加耐热性，对于固定流动沙丘从而起到防风固沙、适应沙漠干旱环境等方面发挥着重要作用。目前为止关于植物自身参与沙套发育形成的机制还未见报道。我们前期研究中发现：糖代谢是最重要的调控沙套发育的因素之一，糖转运蛋白基因SpSWEET与沙套发育密切相关。故本项目旨在研究羽毛针禾糖转运蛋白基因SpSWEET在沙套发育过程中的重要功能，重点分析其对根毛发育及糖组分和含量的影响，探索其参与GA信号调控沙套发育的机制。拟开展如下工作：SpSWEET基因及其启动子的克隆和表达特征分析；SpSWEET蛋白的亚细胞定位分析；SpSWEET在拟南芥突变体中的功能互补分析；SpSWEET在沙套发育中的功能分析；SpSWEET参与糖转运的功能分析；SpSWEET参与GA信号转导路径的调控分析。本研究为解析羽毛针禾沙套的形成及其适应极端干旱的机制提供重要参考。

Stipagrostis pennatais is an important desert pioneer plant and plays significant roles in sand-fixing and extreme-drought environment adaptation, by its special rhizosheaths to protect the roots and increase the heat-tolerance. Currently, studies on the mechanism of rhizosheath formation from the plant itself aspect are rarely reported. Our previous results showed that glucose metabolism is one of the most important factors in regulating the development of rhizosheath, and that the sugar transporter gene SpSWEET is closely related to rhizosheat formation. Thus, the purpose of this project is to study the important function of SpSWEET in rhizosheath development, with the focus on analyzing the effects of SpSWEET on root hair development and sugar composition and content, and to explore the mechanism of SpSWEET regulating rhizosheath formation by participating in GA signaling. The following investigations are planned to be performed: cloning and expression characteristics analysis of SpSWEET gene and the promoter; subcellular localization of SpSWEET protein; genetic complementary analysis of SpSWEET in Arabidopsis T-DNA insertion mutants; functional analysis of SpSWEET in rhizosheath development and sugar transport; regulatory analysis of SpSWEET involving in GA signal transduction pathway. This study will provide an important references for understanding the important function of SpSWEET in rhizosheath formation and for elucidating the mechanism of S. pennatais plants adaptating the extreme-drought environment.