摘要ERF (ethylene responsive factors)是植物AP2/ERF转录因子超家族中的一个亚家族，已被证明和植物的生长发育，防御反应、压力信号系统有关。为了提高植物对逆境的抗性，我们需要了解ERF的基本生物学信息，从而可通过后期的基因工程来增强植物的抗逆性。据已报道的番茄ERF转录因子家族的基因表达信息，我们从番茄中筛选得到SlERF26基因，并根据其基因序列设计特异引物，利用RT-PCR方法从野生型番茄AC++中克隆得到了该基因的cDNA全长序列。并利用生物学网站、软件等对该序列进行生物信息学分析。序列分析表明，SlERF26基因全长821 bp，此中开放阅读框为537 bp，编码178个氨基酸。蛋白质结构功能域、理化性质分析表明，其编码的氨基酸具有ERF蛋白家族典型的AP2结构域。蛋白分子量为19.26 kD，理论等电点pI为4.82，脂溶指数（Aliphatic index）为66.01，疏水性平均值（Grand average of hydropathicity ）: -0.483，证明该蛋白是亲水性脂溶蛋白。磷酸化位点预测显示该蛋白具有多个磷酸化位点，亚细胞定位分析显示该蛋白定位于细胞质。二级结构预测分析显示该蛋白含29.78%的α-螺旋、13.48%的延伸链、6.74%的β-转角和50%的无规卷曲。多重序列比对和系统进化分析表明，SlERF26蛋白与其他植物ERF蛋白具有较高的同源性。这些结果为进一步研究SlERF26在番茄发育和胁迫响应中的功能作用奠定了基础。69172
毕业论文关键词：番茄 ERF转录因子 SlERF26 生物信息学分析
Cloning and expression analysis of a stress responsive factor SlERF26 in tomato (Solanum lycopersicum)
ERF (Ethylene responseive factors) is a subfamily of plant transcription factor superfamily, which has been shown to be related to plant growth and development, defense response and stress signaling systems. In order to improve the resistance of plants to stress, we need to understand the basic biological information of ERF, so as to enhance the resistance of plants by genetic engineering. According to the reported gene expression information of the tomato ERF transcription factors, we selected a gene named SlERF26 and cloned its whole length cDNA sequence from the wild type tomato AC++ by RT-PCR using the specific primers. The bioinformatics analysis of the sequence was carried out using biological sites, softwares and so on. Sequence analysis showed that the length of SlERF26 gene is 821 bp including an open reading frame of 537 bp, and the open reading frame encoding 178 amino acids. The analysis of protein structure, physical and chemical properties showed that the encoded amino acids have a typical AP2 domain that belongs to ERF protein family. SlERF26 protein has a molecular weight of 19.26 kD, the theory electric point is 4.82 and grand average of hydropathicity is -0.483, aliphatic index is 66.01, indicating that the protein is hydrophilic lipid soluble protein. Phosphorylation site prediction showed that the protein had a number of phosphorylation sites, and subcellular localization analysis revealed that the protein was located in the cytoplasm. Protein secondary structure prediction analysis showed that SlERF26 protein contained 29.78% alpha helix, 13.48% extended strand, 6.74% beta turn, and 50% random coil. Multiple sequence alignment and phylogenetic analysis showed that SlERF26 protein had high homology with other plant ERF proteins. These results lay a foundation for further research on the functional role of SlERF26 gene in tomato development and stress response.
Key words: Solanum lycopersicum; ERF transcription factors; SlERF26; bioinformat ics analysis