芥蓝Aux/IAA家族基因生物信息学与表达分析

Bioinformatics and expression analysis of Aux/IAA family gene in Chinese kale

为更好地理解芥蓝生长素(indole-3-acetic acid,IAA)的响应途径及揭示Aux/IAA基因家族在芥蓝生长和抗盐胁迫中的功能,本研究利用生物信息学的方法从芥蓝基因组中鉴定到了41个Aux/IAA家族基因。系统进化分析结果表明,芥蓝Aux/IAA基因家族成员分布于9条染色体上,在染色体C01和C05上分布的基因最多,各有6个;该家族基因编码的蛋白质的氨基酸残基数在128~427之间,大多数为亲水性蛋白,仅有2个疏水性蛋白。亚细胞定位预测结果表明,Aux/IAA家族成员多位于细胞质、细胞核和叶绿体上。实时荧光定量聚合酶链式反应(real-time quantitative polymerase chain reaction,qRT-PCR)结果表明,芥蓝Aux/IAA基因家族部分成员对生长素(IAA)、脱落酸(abscisic acid,ABA)、油菜素内酯(brassinosteroids,BR)处理存在不同程度的响应,说明芥蓝Aux/IAA基因家族很可能参与植物激素信号的传导。此外,经过盐胁迫处理后,芥蓝BoIAA19-1与BoIAA2-1的表达量在处理前期均显著上调,预示Aux/IAA基因在芥蓝响应逆境的过程中也可能发挥作用。本研究结果为进一步研究Aux/IAA基因家族在芥蓝生长和抗性平衡中的功能奠定了理论基础。

To better understand the indole-3-acetic acid(IAA)response pathway and explore the specific functions of Aux/IAA gene family in the growth of Chinese kale and in response to salt stress,forty-one Aux/IAA genes were collected and analyzed by bioinformatics methods from Chinese kale genome.Phylogenetic analysis showed that the Aux/IAA genes of Chinese kale were distributed on nine chromosomes and the most genes were distributed on chromosome C01 and C05 including six members,respectively.The number of the amino acid residues of proteins encoded by Aux/IAA genes ranged from 128 to 427,and most of them were hydrophilic proteins,and only two were hydrophobic proteins.The subcellular localization analysis indicated that the Aux/IAA family members were mostly located in cytoplasm,nucleus and chloroplast.The results of real-time quantitative polymerase chain reaction(qRT-PCR)showed that several Aux/IAA genes of Chinese kale responded to IAA,abscisic acid(ABA)and brassinosteroids(BR)treatments,which suggested that the Aux/IAA gene family was probably involved in plant hormone signal transduction process.Additionally,under salt stress treatment,the expression of BoIAA19-1 and BoIAA2-1 genes in Chinese kale were significantly up-regulated during the early treatment stage,indicating that Aux/IAA genes may also play roles in response to diverse environmental stresses.The results of this research lay theoretical foundations for further exploring the function of the Aux/IAA gene family in the growth and resistance balance of Chinese kale.