水稻CO39品种及其5个近等基因系对稻瘟病感染应答的转录组分析

发布时间：2018-02-11 08:46

本文关键词： 水稻(Oryza sativa L.) 转录组测序近等基因系基因差异表达　出处：《福建农林大学》2016年硕士论文　论文类型：学位论文

【摘要】：水稻(Oryza sativa L.)是最重要的粮食作物之一,也是世界1/2以上人口的主食。但由真菌Magnaporthe Oryzae侵染引起的稻瘟病可以造成水稻的大幅度减产,严重时甚至颗粒无收。水稻稻瘟病广泛的分布在温带和热带水稻种植区。虽然对抗性基因的遗传研究已经进行了数十年,但选育出具有广谱抗性的水稻新品种的研究仍未见报道。其重要原因是人们尚未完全了解稻瘟病菌对水稻的侵染机制。本文以感病亲本品种C039及其抗病近等基因系C101LAC、C101A51、C101PKT和C105TTP-4L23(简称CN-1、CN-2、CN-4a和CN-4b)为材料,以稻瘟病菌高毒力生理小种GUY11为胁迫因子,应用RNA-seq技术,分析稻瘟病菌GUY11侵染下各NILs品种中的基因差异表达,取得如下研究结果。1.基因差异表达分析表明在GUY11侵染24h,供试5个抗病NILs品种中的差异表达基因(DEGs)明显多于感病亲本C039,且相同DEG只有3个。而在侵染的48h下,供试6个品种相同差异表达基因的数量增多,说明不同水稻品种在GUY11侵染24h时分子应激的表现不同,到侵染的48h相同趋多,进一步反映是稻瘟病菌侵染24h是水稻应激防御的关键期。2.GO富集分析表明,在5个抗病NILs中的DEGs有16个共同的GO term富集,包括胁迫应激、光合作用、次级代谢等。同时,在高抗品种CN-4b的DEGs有82isoforms,远多于其他4个NILs品种.而且也在CN-4b中发现了若干个起重要作用的上调表达基因,如LOC_Os04g56910.3.对重要基因家族分析表明,GUY11侵染下感病亲本C039中的WAK基因未见差异表达,但在5个NILs中均检测到WAK基因的差异表达,这可能导致两者间抗稻瘟病能力的差异。在C039和5个NILs中均检测到WRKY基因的差异表达,这也说明WRKY基因家族功能的多样性。在抗病的5个NILs中发现一些C039所没有的差异表达WRKY。如在CN-4b中检测到WRKY96的高表达,而且前人的研究也发现该基因的高表达与水稻抗病原菌侵染有关。同时差异表达基因的功能模块分析表明,在5个NILs中WRKY基因的共表达。但C039品种的一个WRKY基因与CPN1基因共表达,而CPN1会抑制C039的防御能力。本文研究结果表明稻瘟病菌侵染下,感病亲本C039及其5个抗病NILs中被诱导表达的基因数量、功能、共表达模块等的不同,导致供试品种间具有不同的抗稻瘟病能力。
[Abstract]:Oryza sativa L.) is one of the most important food crops and a staple food for more than 1/2 people in the world. However, the blast caused by the fungus Magnaporthe Oryzae can greatly reduce the yield of rice. Rice blast is widespread in temperate and tropical rice growing areas, although genetic research on resistance genes has been under way for decades. However, studies on the selection of new rice varieties with broad spectrum resistance have not been reported. The important reason is that people have not fully understood the infection mechanism of rice blast fungus. In this paper, the susceptible parent C039 and its nearly resistant genes have not been fully understood. The materials were C101LACU C101A51PKT and C105TTP-4L23 (CN-1C2CN-2CN-4a and CN-4b). Using GUY11 as stress factor, RNA-seq technique was used to analyze the differential expression of genes in various NILs cultivars infected with GUY11. The results were as follows: 1. Gene differential expression analysis showed that the differentially expressed genes of 5 resistant NILs varieties were significantly higher than that of susceptible parent C039 in 24 h of GUY11 infection, and only 3 of the same DEG were found at 48 h after infection. The number of the same differentially expressed genes increased in 6 varieties, which indicated that the molecular stress of different rice varieties was different at 24 h after GUY11 infection, and the number of different rice varieties was the same at 48 h after GUY11 infection. The further response was that 24 h infection was the key period of rice stress defense. 2. Go enrichment analysis showed that there were 16 common go term enrichment in 5 resistant NILs, including stress, photosynthesis, secondary metabolism and so on. There were 82isoforms in DEGs with high resistance to CN-4b, much more than the other four NILs varieties. Several up-regulated expression genes were also found in CN-4b. For example, LOCOs04g56910.3.The analysis of important gene families showed that there was no differential expression of WAK gene in susceptible parent C039 infected with GUY11, but the differential expression of WAK gene was detected in 5 NILs. This may lead to the difference of resistance to rice blast. The differential expression of WRKY gene was detected in C039 and 5 NILs. This also indicates the diversity of the function of the WRKY gene family. Some differential expressions of WRKY. such as the high expression of WRKY96 in CN-4b were found in 5 resistant NILs, which were not found in C039. Moreover, previous studies have also found that the high expression of the gene is related to the resistance of rice to pathogen infection, and the functional module analysis of the differentially expressed gene shows that, The co-expression of WRKY gene in 5 NILs, but one WRKY gene co-expressed with CPN1 gene in C039 variety, and CPN1 could inhibit the defense ability of C039. The number, function and co-expression modules of the induced genes in susceptible parent C039 and its five disease-resistant NILs resulted in different resistance to rice blast among the tested varieties.
【学位授予单位】：福建农林大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：S435.111.41

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