脱落酸调控小橡胶粒子蛋白基因表达的分子机制

项目名称： 脱落酸调控小橡胶粒子蛋白基因表达的分子机制

项目编号： No.31471169

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 生物科学

项目作者： 郭冬

作者单位： 中国热带农业科学院热带生物技术研究所

项目金额： 84万元

中文摘要： 乙烯利刺激割胶技术对橡胶增产效果显著，但长期使用会造成橡胶树发生死皮、过早衰老和干胶含量下降等弊病，给天然橡胶的生产带来严重负面影响，寻找新型的高产、高效、安全刺激剂已经成为天然橡胶生产中面临的重要课题。已有研究表明脱落酸（ABA）处理成龄未开割橡胶树树干能增加胶乳产量。小橡胶粒子蛋白（SRPP）是橡胶生物合成的关键因子，具有促进胶乳产量增加、提高橡胶合成速率的作用。我们前期研究发现ABA可以显著提高SRPP基因启动子转录活性，推测ABA可能通过促进SRPP转录水平的提高，进而增加橡胶的生物合成，但具体调控机制尚不清楚。本研究将运用生化与分子生物学技术，鉴定SRPP启动子中ABA应答的顺式作用元件和与其互作的转录因子，研究转录因子与SRPP之间的调控关系，阐明ABA调控SRPP的分子机制，为更深入了解橡胶生物合成的调控机制打下基础，为将来应用生物技术提高天然橡胶的产量提供理论依据。

中文关键词： 转录因子；调控；脱落酸；小橡胶粒子蛋白；橡胶树

英文摘要： Natural rubber (NR) is a renewable important strategic material and industrial raw materials. More than 98% of NR in the world come from Hevea brasiliensis. By now, the production of NR is less than one fifth of consumption and the cultivated area is limited in our country. Therefore, improving the rubber yield became the main way for China's current NR production. The traditional method of rubber tree varieties breeding cycle is long, and the effect is slow. Ethylene, as a stimulant of latex production in Hevea brasiliensis, has been widely used in commercial latex production. Intense ethylene stimulation would eventually lead to tapping panel dryness (TPD). Once the TPD occurs, the tapping incision is partly or entirely blocked and the amount of latex production is significantly decreased or stops completely，leading to severe loss in natural rubber production around the world. So, an alternative stimulant instesd of ethylene is in great needs in natural rubber production. Although significant progress has been made on natural rubber biosynthesis and regulation,the molecular mechanism underlying the regulation of natural rubber biosynthesis remain largely unknown. In H. brasilliensis, small rubber particle protein (SRPP) is a key gene involved in rubber biosynthesis. Recent studies have shown that bark treatments with abscisic acid (ABA) cold induce increase latex yield in mature untapped rubber trees.Our previous study found that ABA can significantly improve the small rubber particle protein gene promoter transcription activity。We suspect that ABA increase rubber biosynthesis may through promoted the improvement of the SRPP transcription level, but the specific mechanism is not clear yet.Through this study will focus on the molecular mechanisms of SRPP responsed to ABA. hese researches should enable us to understand further the expressional regulation mechanism of SRPP in natural rubber biosynthesis in Hevea brasiliensis, which may be useful in developing new stimulus to stimulate latex yield in the production of natural rubber.

英文关键词： transcription factor;regulation;abscisic acid;small rubber particle protein;Hevea brasiliensis