大麦2H染色体在小麦遗传背景中表达及互作模式研究

Wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) are two of the most important cereal crops worldwide. The hybridization of wheat and barley makes it possible to transfer desirable genes and traits, such as earliness, tolerance to biotic and abiotic stresses, and various nutritional parameters, from barley to wheat. But for some reasons, there didn't any reports about it practically. A set of materials include wheat-barley 2H addition line, wheat-barley 2H substitution line 2H(A), 2H(2B) and 2H(2D) have got in our previous NSFC program. During the process of alien germplasm introduced into wheat genetic backgroud, extensive genetic variations of genome structure and gene expression could be induced in wheat. To understand genetic changes associated with introduction of barely chromosome 2H into wheat genome, a set of barley Betzes, wheat CS, wheat-barley 2H addition line, wheat-barley 2H substitution line 2H(2A), 2H(2B) and 2H(2D) were planed to analyze by fluorescence AFLP. To understand epigenetic variations associated with introduction of barely chromosome 2H into wheat genome, fluorescence MSAP detection system were managed to construct based on fluorescence AFLP. To understand gene expression characteristics associated with introduction of barely chromosome 2H, we try to use the fluorescence cDNA-AFLP to analyse the different expression of a set of barley Betzes, wheat CS, wheat-barley 2H addition line, wheat-barley 2H substitution line 2H(2A), 2H(2B) and 2H(2D) . If 2-D and iTRAQ technology was used for differential proteomics analysis on above materials, we can understand the protein expression differences associated with introduction of barely chromosome 2H in wheat background. This research will abundance our knowledge on how barely chromosome 2H worked with wheat in its background. It will have great use both theoretically and practically for enlarge the wheat genetic variation and culture new strains of wheat.

小麦（Triticum aestivum L.）和大麦（Hordeum vulgare L.）为同属于小麦族(Triticeae)的两种非常重要且广泛种植的粮食作物。大麦具有抗逆性强、品质好等诸多优良性状，研究表明大麦2H染色体对小麦第二部分同源群染色体有很好的遗传补偿能力，位于该长臂上的Isa-H1基因在小麦遗传背景下表达良好，能够改善小麦淀粉和蛋白品质。本研究拟以大麦Betzes、小麦CS、小-大麦2H异附加系、小-大麦2H异代换系2H(2A)、2H(2B)、2H(2D)为材料，建立和完善AFLP、MSAP、cDNA-AFLP和蛋白质组检测体系，从基因组水平、基因组表观遗传学水平（DNA甲基化）、转录水平及蛋白质组水平研究大麦2H染色体导入到小麦遗传背景后的表达模式及相互作用，解析大麦2H染色体和小麦遗传背景相应水平的变化，探究小麦品质改善机理，为培育高产优质抗逆小麦新品种奠定基础。

小麦（Triticum aestivum L.，2n = 6 × = 42）和大麦（Hordeum vulgare L.，2n = 2 × = 14)是世界上两大重要的麦类作物，通过小麦和大麦的远缘杂交，可以将大麦的优良基因及其相应性状导入小麦，如早熟、耐生物和非生物胁迫及各种品质性状。. 将大麦基因转移至小麦遗传背景的过程中，会引起小麦基因组结构及基因表达的广泛遗传变异。为了了解大麦2H染色体导入小麦后基因组结构的变异，项目采用荧光AFLP方法对大麦Betzes，小麦CS, 小-大麦2H异附加系、异代换系2H(2A)、2H(2B)、2H(2D)这一整套材料进行分析。64对引物组合在大麦中获得了3157个条带，其它材料获得了4736个条带。AFLP扩增类型表明，附加系中检测到了消减和激活位点，代换系基因组结构几乎无变化。同时还检测到了多条大麦2H染色体及小麦2A、2B、2D染色体特异的AFLP片段，经回收测序后，将AFLP分子标记转换成STS分子标记并进行验证，共获得大麦2H染色体特异的AFLP-STS分子标记2条，小麦2A、2B、2D染色体特异的AFLP-STS分子标记各1条。. 为了了解由大麦2H染色体导入而引起的小麦基因组的表观遗传学变异，在荧光AFLP检测的基础上构建了荧光MSAP检测体系，对大麦Betzes，小麦CS, 小-大麦2H异附加系及异代换系2H(2A)、2H(2B)、2H(2D)这套材料的基因组甲基化模式进行研究分析。MSAP结果表明，大麦2H染色体导入引起了小麦基因组的甲基化变异，同时大麦2H染色体本身也检测到了甲基化的升高。. 为了了解由大麦2H染色体导入所引起的基因表达差异，通过荧光cDNA-AFLP对大麦Betzes，小麦CS, 小-大麦2H异附加系及异代换系2H(2A)、2H(2B)、2H(2D)这套材料进行了基因表达差异分析，分离和克隆了大量差异表达基因，明确了大麦2H染色体在小麦基因背景中的表达模式。.利用iTRAQ技术研究由大麦2H染色体导入所引起的蛋白表达差异，并对对以上材料进行差异蛋白质组学分析，目前为止，共鉴定出589个蛋白。. 通过以上研究，解析了大麦2H染色体和小麦遗传背景相应水平的变化，为进一步利用外源种质改良小麦品质及抗性等奠定基础。