基于Ecotilling技术的象草木质素合成基因优异等位基因发掘

项目名称： 基于Ecotilling技术的象草木质素合成基因优异等位基因发掘

项目编号： No.31302025

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 农业科学

项目作者： 吴娟子

作者单位： 江苏省农业科学院

项目金额： 23万元

中文摘要： 象草是优质饲料作物，也是极具潜力的木质纤维素类能源植物。象草细胞壁可降解性影响其饲用品质和生物质能的糖转化效率。研究表明木质素是限制细胞壁降解的关键因素。国内外象草木质素合成的分子生物学研究报道不多，亟待加强。本项目拟在象草中建立高通量检测等位基因变异的Ecotilling技术平台，以具有广泛遗传差异的130份象草为材料，利用同源基因克隆技术和已知基因信息克隆象草木质素合成途径的5个关键基因（4CL、COMT、F5H、CAD和CCR），利用Ecotilling技术分析象草群体中这5个基因的等位基因变异，并通过细胞壁可降解性评价指标的多次测定和评估，结合群体遗传结构分析和这5个基因等位基因多态性分析、LD分析和单倍型分析开展基于候选基因策略的关联分析。旨在发掘象草中与细胞壁可降解性相关的关键基因及其优异等位基因变异和功能单倍型，为象草品种改良提供参考依据，具有重要的理论意义和实践价值。

中文关键词： 象草；细胞壁；木质素；基因表达；

英文摘要： Elephant grass (Pennisetum purpureum Schum.) is an excellent forage crop, and a promising lignocellulosic energy crop. Lignin is the critical factor for cell wall degradability which affect not only feed quality but also cell wall sugar conversion efficiency. To date, the genetics and molecular biology research on lignin synthesis of elephant grass is very insufficient. In this study, we develop Ecotilling technique to detect allelic variation in elephant grass and clone five genes (4CL, F5H, COMT, CCR and CAD) involved in lignin synthesis of elephant grass. The cDNA encoding full-length of COMT and F5H genes will be cloned from cDNA prepared from leaf tissue using RT-PCR and RACE methods and the DNA sequence informations of 4CL, CCR and CAD will be obtaineded from NCBI. And a set of 130 elephant grass lines are chosen for allelic varieties genotyping and cell wall degradability phenotyping. Furthmore, based on the population structure analysis, association analysis is conducted to identify the functional allelic variations and functional haplotypes related to cell wall degradability within each of the five genes by logistic model. The results obtained in this study will help us to understand the genetic and molecular mechanism of lignin synthesis and provide theoretical guidance for breeding program in elephant

英文关键词： Cenchrus purpureus；cell wall；lignin；gene expression；