茶树csn-miR156e/h非生物胁迫应答机制的研究

Tea plant [Camellia sinensis (L.) O.Kuntze] is one of the important economic crops in China. Abiotic stresses are more likely to bring damage to tea plant, which could seriously affects the yields as well as the economic benefits. To figure out the the mechanism of abiotic resistence has become the primary task of tea breeding. miR156 from plant have been reported to play important roles in growth and development process and actively involved in stress response..On this basis, the project focuses on csn-miR156e/h to study its expression patterns in response to low-temperature, drought, high-salinity stress and even cross-stresses, to make clear its function to different adverse environmental conditions. To reveal abiotic stress response mechanism of csn-miR156e/h by over-express and inhibit-express of csn-miR156e/h in the model plant genetic transformation system and making comprehensive analyses suck like phenotypes, physiological changes, the expression level of related miRNAs and mRNA genes, and the accumulation differences of metabolites. The research will provide new experimental support in adversity biology study of tea plant, by enriching the study of signal and regulation pathway such like miR156-miR172/157 and miR156-SPLs-DFR. Moreover, the project will serve new identification index in choosing high anti-adversity tea plant cultivars in selection breeding.

茶树[Camellia sinensis (L.) O.Kuntze]是我国重要的经济作物，非生物胁迫严重影响着茶树的生长发育和茶叶的产量及品质。茶树抗逆机理的研究已成为良种选育的首要任务。研究发现，miR156对植物生长发育有重要调控作用且积极参与逆境应答。.本项目以茶树csn-miR156e/h为研究对象，研究其在干旱、低温、高盐、以及交叉胁迫下的表达情况，明确其对非生物胁迫的应答功能；借助模式植物的遗传转化，进行过表达和抑制表达的对比研究，综合分析表型性状、生理指标、相关miRNA表达、靶基因及其他相关基因表达、代谢产物积累等差异情况，阐明csn-miR156e/h对非生物胁迫的应答机理；丰富miR156-miR172/157等信号通路及miR156-SPLs-DFR等调控途径的研究，为茶树逆境生物学研究提供新的实验支撑；同时，研究结果可为抗逆茶树品种的选育提供一定的借鉴指标。

茶树[Camellia sinensis (L.) O.Kuntze]是我国重要的经济作物，非生物胁迫严重影响着茶树的生长发育和茶叶的产量及品质。茶树抗逆机理的研究是良种选育的首要任务。研究发现，miR156对植物生长发育有重要调控作用且积极参与逆境应答。作为植物界最为古老且高度保守的miRNA家族，miR156积极参与赤霉素途径、育性、发育阶段转变等生理过程。我们和其他研究人员也发现，miR156及其靶基因SBP/SPL（SQUAMOSA promoter-binding protein-like）在逆境应答方面也起到重要的调控作用。.本项目首先研究CsmiR156在干旱、高盐和低温下的表达情况，确定其参与逆境应答；借助拟南芥的遗传转化，明确其调控通路；其次，基因组水平全面分析其靶基因SBP转录因子家族；另外，关联分析小RNA、转录组测序和特征性代谢产物的含量，明确CsmiR156—TF—多酚类调控；研究多酚类合成途径中的关键酶花青素还原酶的酶学功能，全面阐释CsmiR156参与调控的网络调控。我们发现，茶树CsmiR156积极响应干旱、高盐和低温胁迫；CsmiR156过表达拟南芥侧根多且长，种子中EC 和寡聚 PA 含量显著增多，大部分黄酮醇糖苷减少；CsmiR156参与调控的模式推测为CsmiR156—CsaSBP14 (CSA031667)-C；靶基因SBP转录因子家族进行了基因组范围的生物信息学分析，明确CsmiR156的靶基因CsaSBP14处于CsSBP分组的第2组。另外，儿茶素和原花青素合成途径中的关键酶类茶树花青素还原酶的还原酶酶活和异构酶酶活的功能得到了全面的解释。.本项目证实并揭示了CsmiR156的抗逆机理，为茶树逆境生物学研究提供新的实验支撑；同时，研究结果为抗逆茶树品种的选育提供了一定的借鉴指标。