随着全球资源的日益贫乏和气候灾害的日趋严重，植物的抗逆性研究显得愈来愈重要。好好芭（Simmondsia chinensis (Link) Schneider）是原产于北美Sonoran沙漠的一种雌雄异株的多年生常绿灌木，具有极强的抗旱、耐瘠薄、耐高温特性。研究发掘好好芭抗逆基因，用于作物遗传改良，提高植物自身的水分利用效率和耐旱性，对于减少农业投入、增加作物产出和改善生态环境具有重要意义。好好芭分子生物学方面的研究开始于20世纪90年代，最主要的成果集中于好好芭油合成相关基因的研究。好好芭抗旱及抗寒相关研究主要由本实验室进行，通过抑制性消减杂交方法获得了386个干旱诱导特异性表达的ESTs，并对好好芭抗旱及抗寒性鉴定的生理指标和微繁殖技术进行了研究。本研究拟克隆好好芭抗旱相关基因，在分子水平上研究好好芭的抗旱响应机制。通过对好好芭抗逆蛋白质组学和抑制性消减杂交研究，分析诱导特异性表达ESTs，克隆了抗逆相关基因，开展烟草基因转化、鉴定并评价这些基因的功能，以期揭示好好芭的抗逆机理。主要研究结果如下：1. 利用2-DE和质谱分析对好好芭干旱和低温胁迫条件下叶片的蛋白质组学进行研究，获得胁迫条件差异表达点152个，其中表达差异4倍以上者132个，使用MS-TODF对其中30个点进行鉴定，获得了20个胁迫条件下差异表达的蛋白点身份。从获得的信息中发现，好好芭胁迫应答过程涉及光合系统、多种激素途径、ROS信号途径、蛋白磷酸酶和HSPs家族蛋白等。同时还发现干旱和低温共响应蛋白6个，并对其功能进行了初步分析。2. 构建了好好芭叶片在低温胁迫条件下的正向及反向SSH文库。正向SSH库随机选取100个EST进行测序，对拼接获得的22个好好芭低温胁迫上调基因的ESTs。与前期的干旱胁迫正向SSH文库数据进行比对分析，发现干旱和低温共响应基因4个。综合分析好好芭干旱条件下抑制性消减杂交cDNA文库及2-DE所得数据，对好好芭胁迫应答涉及的信号、基因及代谢途径进行了分析讨论。这些研究结果，为深入研究好好芭抗逆响应机理提供了新的基础。3. 在对本实验室获得的好好芭干旱胁迫条件下抑制性消减杂交cDNA文库ESTs数据进行分析的基础上，通过RACE技术克隆了抗旱相关基因ScCu/ZnSOD和ScMnSODORF的序列。并研究了它们在不同胁迫条件下的mRNA表达模式。4. 对转ScMnSOD、ScPIP1基因的烟草植株进行了生理和分子水平的研究，发现ScMnSOD的转入有效地提高了烟草对干旱的耐受能力和细胞膜的修复能力，并获得了转ScMnSOD基因的烟草抗旱植株。对转ScPIP1的烟草植株进行形态观察和生理检测发现，ScPIP1作为膜定位水通道蛋白使第二代转基因植株的气孔开度及密度有明显的变化，影响其抗旱能力。本研究为在蛋白质及核酸水平上研究好好芭胁迫应答机理开创了新平台，为深入研究好好芭抗逆响应机理提供了新的基础。对进一步认识好好芭的逆境响应机理，充分发掘和利用好好芭的优异基因资源都是有益的。这对进一步鉴定好好芭特异性抗旱相关基因、作物改造，以及推动干旱、半干旱地区的农业发展和生态环境的改善都具有积极的作用。

Jojoba (Simmondsia chinensis (Link) Schneider) is a perennial evergreen shrub native to the Sonoran Desert of the southwestern America. The plant has a great resistance to drought and high temperature. It is significant to study and explore Jojoba stress-resistant genes for the genetic improvement of crops, the enhancement of plants’ water usage efficiency and drought-resistance, which would have important meanings for the reducing of agricultural investment, the increase of crop output and the improvement of ecological environment. The molecular biology research on Jojoba was first carried out in the 1990s.The research results are mainly focused on Jojoba oil synthesis related genes. The study on Jojoba’s resistance of drought and cold is conducted in this laboratory. 386 drought-induced specifically expressed ESTs were gained through SSH (suppression subtractive hybridization). The indicators to Jojoba’s resistance of drought and cold were identified and micropropagation of Jojoba was studied. This study was aimed at cloning Jojoba drought-resistance related genes and clarifying the mechanism of Jojoba drought responses at the molecular level. Through the analysis of 386 drought-induced specifically expressed ESTs, 2 drought-resistance related genes with full length were cloned, and the genes were transformed into Arabidopsis thaliana to identify and evaluate their functions. Meanwhile, Proteomics on stress resistance of plants and SSH were performed in this laboratory to reveal the mechanism of Jojoba’s resistance to stress. The main findings are as follows:1. Proteomics of Jojoba leaves under the conditions of drought and cold were studied through 2-DE and mass spectrometry analysis, and 20 differentially expressed protein spots were identified. This would initiate a new platform for studying the mechanism of Jojoba stress responses at the level of protein. It was found that the process of Jojoba stress responses involved photosynthetic system, several hormone pathways; ROS signal pathways, protein phosphatases and HSPs family proteins. 6 proteins responsive to drought and cold were discovered, and their functions were preliminarily analyzed. 2. Jojoba SSH cDNA library was obtained under the stress of cold, and there were 22 ESTs of up-regulated genes. Combined with previous data, these 22 ESTs were analyzed, and 5 genes responsive to drought and cold were discovered. Considering the data of SSH and 2-DE, this study predicted the signals, genes and pathways related to Jojoba stress responses, and collected important information about the mechanism of Jojoba stress responses at molecular and protein levels, thus deepening the understanding of Jojoba stress response mechanism. 3. Based on the analysis of drought-induced specifically expressed ESTs,2 drought-resistance related genes of Jojoba with ORFs, including ScCu/ZnSODand ScMnSOD were cloned. The mRNA expression patterns of these genes were examined under different stress conditions.4. Studies on tobaccos transformed with ScMnSOD and ScPIP1 were conducted at physiological and molecular levels, and the results showed that tobaccos transformed with ScMnSOD have a higher resistance to drought and a better repair capacity of membrane. Physiological detection on tobaccos transformed with ScPIP1 was carried out and the results showed that ScPIP1 which functioned as membrane-located aquaporin significantly affected the stomatal aperture and density of the second-generation transgenic plants. The ability of the second-generation transgenic plants to resist drought was enhanced and plants with drought-resistance were obtained. This study is beneficial for the further understanding of the mechanism of abio-stress response in Jojoba, exploring and usage of Jojoba favorable genes. It would have a positive effect on the further identification of Jojoba specific drought-resistance related genes and crop transformation, which would help to boost the agricultural development in arid and semi-arid areas and the improvement of ecological environment.