番茄WRKY转录家族生物信息学分析及部分抗逆相关基因鉴定

发布时间：2018-05-14 05:05

本文选题：番茄 + WRKY　；参考：《东北农业大学》2017年硕士论文

【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。
[Abstract]:Tomato has rich nutritional value, strong adaptability, easy cultivation and high yield. Therefore, tomato is an important vegetable in the world and plays a major role in vegetable production. But in the process of tomato growth, it is usually affected by the adverse natural environment, which leads to the decline of the yield. Therefore, it is of great significance to study the effects of stress on the growth of tomato. In this paper, the whole genome mining and bioinformatics analysis of WRKY family of tomato transcription factors related to stress resistance were carried out, and the expression patterns of some genes under stress were studied. By bioinformatics analysis, 81 members of tomato WRKY family were identified and divided into 3 families according to their WRKY domain and zinc finger structure. The second group can be divided into 5 subfamilies according to its amino acid sequence. Except for tomato chromosome 11, there were no WRKY transcription factors, but all other chromosomes were distributed. Only Sl WRKY19Sl WRKY20 family members do not contain introns, while the other members contain 2 ~ 5 introns. The WRKY domain of tomato was highly conserved, and only 10 WRKYGQK were mutated. The tissue specific expression patterns of 6 typical WRKY transcription factors were analyzed in 10.2% of the WRKY family. The results showed that these genes were expressed in root, stem, leaf, flower and fruit. However, there were differences in the expression levels of different genes in the same tissue, and there were also differences in the expression levels of SL WRKY13 and SL WRKY24 in different tissues. The expression of SL WRKY13 and SL WRKY24 in roots and flowers was higher than that in stems, and there was almost no expression of SL WRKY31 in roots and stems. The expression of Sl WRKY50 in leaves was higher than that in flowers, leaves and flowers, and the expression of Sl WRKY62 in roots, leaves and fruits was higher than that in stems, and the highest expression of Sl WRKY63 in roots was found in stems. In stem and fruit, the expression level of Sl WRKY62 and SL WRKY63 gene increased at first, then decreased gradually, while the expression of SL WRKY24 gene decreased significantly in the treatment of salt stress, while the expression level of Sl WRKY13 Sl WRKY31nSl WRKY50 Sl WRKY63 gene increased at first and then decreased gradually in both stem and fruit. The expression of Sl WRKY13 Sl WRKY31 WRKY62 and SL WRKY63 genes in drought stress was up-regulated, and the expression of Sl WRKY24 and SL WRKY50 genes were down-regulated. Under low temperature stress, Sl WRKY13 + Sl WRKY31Sl WRKY50Sl WRKY62 and SL WRKY63 down-regulated the down-regulation of Sl WRKY24 gene expression. The gene silencing of the gene SL WRKY50, which changed significantly in stress response analysis, was found after the gene silencing. The MDA index of the plant under low temperature stress was significantly higher than that of the control plant under the same condition, while the Pro and SOD indexes were significantly decreased, which indicated that the down-regulation of the gene expression could reduce the cold resistance of the plant.
【学位授予单位】：东北农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S641.2

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