【作者】 张红；

【导师】 李景富；

【作者基本信息】 东北农业大学 ， 蔬菜学， 2017， 硕士

【摘要】 番茄具有丰富的营养价值、较强的适应能力、栽培很容易以及很高的产量等特点,因此,番茄是一种重要的世界性蔬菜,在蔬菜生产中占有主要地位。但是番茄在生长的过程中,通常会受恶劣自然环境的影响,导致产量的下降,因此研究逆境胁迫对番茄生长的影响,有着重要的意义。本文主要对番茄与抗逆相关的转录因子WRKY家族进行了全基因组挖掘及生物信息学分析,并且通过对部分基因在逆境胁迫下的表达模式进行研究,获得了该家族中与番茄抗逆应答相关的基因。1通过生物信息学分析,鉴定出了番茄WRKY家族包含81个成员,按其WRKY结构域及锌指结构分为3族,第二族按其氨基酸顺序又可以分为5个亚族。除番茄的11号染色体没有WRKY转录因子,其他染色体上均有分布。仅Sl WRKY19,Sl WRKY20俩个家族成员不含内含子,其他成员都含有2~5个内含子。番茄WRKY结构域是高度保守的,仅有10个WRKYGQK发生了变异,占WRKY家族的10%。2对6个典型WRKY转录因子进行组织特异性表达模式分析,发现这些基因在根、茎、叶、花、果中均有表达,但不同基因在同一组织中的表达量存在差异,同一基因在不同组织中的表达量也存在差异,Sl WRKY13和Sl WRKY24在根和花中的表达量较高,在茎中几乎不表达;Sl WRKY31在根、茎、叶中的表达量大于花和果;Sl WRKY50在根、叶、花中的表达量较高,在茎中几乎不表达;Sl WRKY62在根、叶、果中的表达量较高,在茎中几乎不表达;Sl WRKY63在根中的表达量最高,在茎和果中几乎不表达。3在盐胁迫处理中,SlWRKY13、Sl WRKY31、Sl WRKY50、Sl WRKY62和Sl WRKY63基因的表达水平呈现先上升,然后逐渐下降的趋势,而Sl WRKY24基因的表达则显著下调;在干旱胁迫处理中,Sl WRKY13、Sl WRKY31、Sl WRKY62和Sl WRKY63基因表达上调,Sl WRKY24和Sl WRKY50基因表达下调;在低温胁迫处理中,Sl WRKY13、Sl WRKY31、Sl WRKY50、Sl WRKY62和Sl WRKY63基因表达上调,Sl WRKY24基因表达下调。4对逆境胁迫应答分析中表达量变化较显著的基因Sl WRKY50进行了基因沉默分析,发现该基因沉默后,植株在低温胁迫逆境条件下的MDA指标与相同条件下的对照植株相比显著上升,而Pro和SOD指标显著下降,说明该基因的下调表达可以降低植株的抗寒性。更多还原

【Abstract】 Tomatoes have the characteristics of rich nutrition,wide adaptability,easy cultivation and high output,versatility and so on.Therefore,tomato is an important vegetable in the world.and plays a key role in production.However,in the process of tomato growth,it is usually affected by the harsh natural environment,which leads to the decline of yield,so it is very important to study the effect of stress on tomato growth and development.1.Through the bioinformatics analysis,we identified that the tomato Sl WRKY family contains 81 members,divided into 3 groups according to their WRKY domain and zinc finger structure,and the group 2 can be divided into 5 subgroups according to their amino acid sequence.In addition to tomato chromosome 11,there was no WRKY transcription factor,which was distributed on other chromosomes.Only Sl WRKY19,Sl WRKY20 two family members do not contain introns,other members contain 2~5 introns.Tomato WRKY domain is highly conserved,only 10 WRKYGQK mutated,accounting for 10% of WRKY family.2.Tissue specific expression pattern of 6 typical WRKY transcription factor were analysised.We revealed that these genes,in root,stem,leaf,flower and fruit were expressed,but there are differences in expression of different genes in the same tissues,there are differences in expression of the same gene in different tissues of quantity.The expressions of Sl WRKY13 and Sl WRKY24 was higher in roots and flowers,almost no expression in stem;the expression of Sl WRKY31 in root,stem and leaves was higher;the expression of Sl WRKY50 in root,leaves and flower was higher,almost no expression in stems;the expression of Sl WRKY62 in root,leaves and fruit was higher,almost no expression in stems;the expression of Sl WRKY63 in root was higher,almost no expression in stems and fruit.3.The expression of Sl WRKY13,Sl WRKY31,Sl WRKY50,Sl WRKY62 and Sl WRKY63 were u p-regulated first and then decreased gradually in the salt stress treatment,but the expressionof Sl WRKY24 gene was significantly down regulated;in drought stress treatment,Sl WRKY13,Sl WRKY31,Sl WRKY62 and Sl WRKY63 gene expression was up-regulated,and the expressio n of Sl WRKY24 and Sl WRKY50 was down regulated;At low temperature stress,Sl WRKY13,S l WRKY31,Sl WRKY50,Sl WRKY62 and Sl WRKY63 gene expression was up-regulated,and the ex pression of Sl WRKY24 gene was down regulated.4.We studied the Sl WRKY50 which expression was significantly changed in response to abiotic stress by virus-induced gene silencing(VIGR).It was found that the MDA index of the plants under the low temperature stress was significantly higher than that of the control plants,while the Pro and SOD indexes decreased significantly.The results showed that the down regulated expression of this gene could reduce the cold resistance of plants.更多还原