γ-氨基丁酸转氨酶基因家族在高粱盐胁迫响应中的功能研究

项目名称： γ-氨基丁酸转氨酶基因家族在高粱盐胁迫响应中的功能研究

项目编号： No.31471558

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 食品科学、农学基础与作物学

项目作者： 朱莉

作者单位： 中国农业科学院生物技术研究所

项目金额： 80万元

中文摘要： 高粱是一种重要的粮食、饲料、能源C4模式作物，耐盐性强，适应性广，但其耐盐分子机制的研究相对滞后。γ-氨基丁酸代谢旁路在植物抵御各种逆境胁迫中发挥着重要的作用，但其抗逆分子机制尚未明确，且从该途径解析高粱耐盐机制还是个空白。本实验室前期从耐盐甜高粱中分离鉴定了两个γ-氨基丁酸转氨酶同源基因（SWGABA-Ts），结果表明SWGABA-Ts基因表达均受盐胁迫诱导，其表达模式与高粱品种的耐盐性密切相关，但其在高粱耐盐中的作用机制尚不清楚。本项目拟在此基础上通过RNAi基因沉默、过表达等技术创制高粱转基因突变体材料，对野生型和突变体进行形态鉴定、生理生化检测、代谢物图谱及基因组表达谱方面的比较分析，旨在从功能基因组学水平解析SWGABA-Ts基因在盐胁迫中的生物学功能，为深入研究GABA代谢途径在高粱耐盐分子机理中的作用提供理论依据，也为今后抗逆基因挖掘、作物品质改良、盐碱地开发利用奠定基础。

中文关键词： 高粱；γ-氨基丁酸转氨酶；突变体；功能基因组学；盐胁迫

英文摘要： Sorghum, as an ideal C4 cereal model for food, feed and biomass energy crops, has strong tolerance to salt stress, but the molecular mechanisms underlying the Sorghum salt tolerance are poorly understood. Recent studies indicate that the γ-aminobutyric acid (GABA) metabolism pathway plays a crucial role in plant response to various biotic and abiotic stresses, but the molecular mechanism of GABA metabolism in response to stress remains unclear, and there is not any report to study the salt resistance mechanism from this pathway in Sorghum till now. Two homologous genes of GABA transaminase (SWGABA-Ts) have been previously identified from salt-tolerant Sweet Sorghum in our lab, and the results indicated that the expression levels of SWGABA-Ts were induced by salt stress, with expression patterns closely associated with the salt resistance of Sorghum varieties, but their functions in Sorghum salt-tolerant mechanism remain elusive. In this project,the Sorghum transgenic mutants will be created by RNAi gene silencing,gene overexpressing transgenic technology, respectively, and the comparative analysis between the wild type and mutants will be performed from morphological, physiological and biochemical assay, metabolites profiling analysis and genome-wide transcriptional analysis. The aim of these studies is to elucidate the biological function of SWGABA-Ts genes in response to salinity stress in Sorghum at the perspective of functional genomics. Our studies will not only be helpful to provide a theoretical basis for further studying the molecular mechanism of Sorghum responses to salinity stress, but also has very important practical significance in the excavation of functional genes, the improvement of crop yield and quality, and the effective utilization of saline-alkali soil.

英文关键词： Sorghum;γ-aminobutyric Acid transaminase;Mutants;Functional Genomics;Salt Stress