基于CsPIPs介导的根系水分传输解析CO2加富缓解黄瓜干旱胁迫的生理机制

Cucumber (Cucumis sativus L.) is very sensitive to water status. Drought stress can decrease photosynthetic performance of cucumber leaves, therefore reduce the yield and quality. Our previous studies showed that CO2 concentration enrichment can regulate photosynthetic performance, reactive oxygen scavenging system, metabolic pathway and regulatory network, proteome differential expression and other physiological activities of cucumber seedling leaves to alleviate drought stress, with significant ‘mitigation effect’! However, it is still unclear that how cucumber roots respond to CO2 enrichment through water absorption and transport to improve drought adaptation. Therefore, based on the preliminary determination of proteome of cucumber root system under CO2 enrichment and drought stress by tandem mass tag (TMT) technology, the objective of this project is to analyze the mitigation effect of CO2 enrichment on drought stress to cucumber as following four aspects: (1) functional analysis of differential proteome of cucumber root; (2) cloning, subcellular localization and functional identification of plasma membrane intrinsic proteins of cucumber root (CsPIPs); (3) regulatory mechanism of water transport mediated by CsPIPs; (4) response of CsPIPs to CO2 enrichment and drought stress at transcriptional and proteic levels. The results will clarify the biological mechanism of ‘mitigation effect’ of CO2 enrichment through mechanism of adaptation and regulation maintaining water balance in plant, and provide the theoretical basis and technical parameters for CO2 fertilization of protected vegetables with good quality and high efficiency.

黄瓜对水分状况非常敏感，干旱胁迫导致其叶片光合性能下降、产量和品质降低。本实验室研究结果表明CO2加富可通过调控黄瓜幼苗叶片的光合性能、活性氧清除系统、代谢途径和调控网络、叶绿体蛋白质组差异表达等生理活动来缓解干旱胁迫，具有显著的“缓解效应”！但是CO2加富如何调控黄瓜根系吸收和传输水分来缓解干旱胁迫尚不清晰。因此，本项目在完成CO2加富与干旱胁迫条件下黄瓜根系的蛋白质组学测定的基础上，拟从黄瓜根系差异蛋白质组功能分析、黄瓜根细胞质膜水孔蛋白CsPIPs基因的克隆与亚细胞定位及功能鉴定、黄瓜根细胞质膜水孔蛋白CsPIPs介导的水分传输调节机制、黄瓜根细胞质膜水孔蛋白CsPIPs基因在转录和蛋白水平对CO2加富和干旱胁迫的响应4方面开展研究，以期从CO2加富维持黄瓜体内水分平衡的适应与调控机制角度阐明“缓解效应”的生物学机制，并为设施蔬菜提质增效栽培过程中CO2施肥提供理论依据和技术参数。

本项目在完成CO2加富与干旱胁迫条件下黄瓜根系的蛋白质组学测定的基础上，从黄瓜根系差异蛋白质组功能分析、黄瓜根细胞质膜水孔蛋白CsPIPs基因的克隆与亚细胞定位及功能鉴定、黄瓜根细胞质膜水孔蛋白CsPIPs介导的水分传输调节机制、黄瓜根细胞质膜水孔蛋白CsPIPs基因在转录和蛋白水平对CO2加富和干旱胁迫的响应4方面开展了深入研究，从CO2加富维持黄瓜体内水分平衡的适应与调控机制角度阐明了“缓解效应”的生物学机制，并为设施蔬菜提质增效栽培过程中CO2施肥提供理论依据和技术参数。