山新杨PdPapHSF-A4b基因在胁迫条件下的组织表达模式

Cloning and Tissue-specific Expression Profile of PdPapHSF-A4b in Populus davidiana×P.alba var.pyramidlis in Response to Stresses

为筛选林木抗性基因,培育高抗转基因林木,以山新杨为试材,采用RT-PCR技术克隆获得1359 bp的PdPapHSF-A4b(Potri.014G141400.1)基因cDNA,生物信息学分析表明该基因编码452个氨基酸,该蛋白属于亲水性酸性蛋白。蛋白结构分析发现PdPapHSF-A4b与5个杨树品种的8条HSF序列具有高度一致性。qRT-PCR分析显示,PdPapHSF-A4b在老叶中表达量最高。并发现200 mmol/L NaCl、Na_(2)CO_(3)溶液(pH=10)和聚乙二醇6000胁迫48 h其在根中除NaCl溶液胁迫均上调表达,NaCl、聚乙二醇6000使其在茎尖表达显著上调,只有聚乙二醇6000使其在叶中的表达显著上调;5种植物致病病原真菌胁迫48 h均使其在根内表达显著上调,立枯丝核菌使其在叶中表达显著上调,只有金黄壳囊孢菌使其在茎尖的表达显著下调。受激素诱导48 h,ABA(100μmol/L)诱导在茎尖和根中的表达量均显著上调;受JA(100μmol/L)和SA(100μmol/L)诱导根部表达量均显著上调,叶部的表达量均显著下调,而茎尖部分不显著。结果表明,PdPapHSF-A4b参与了植物抵抗逆境胁迫和激素诱导的信号途径。

In order to screen for the resistance genes in trees and cultivate highly resistant transgenic trees,the hybrid poplar was used as the material and the 1359 bp coding sequence(cDNA)of PdPapHSF-A4b(Potri.014G141400.1)was cloned through the RT-PCR technology.By bioinformatic analysis,this gene encoded 452 amino acids,and the encoded protein was a hydrophilic acidic protein.Protein structure analysis showed that PdPapHSF-A4b had high similarity with eight HSF coding sequences of 5 other populus species.From qRT-PCR assays showed that PdPapHSF-A4b had high expression in the old leaves,and there 200 mM NaCl,Na_(2)CO_(3) solution(pH=10)and polyethylene glycol 6000(PEG 6000;30%m/v)trearments for 48 h up-regulated the expression of NaCl solution the roots.NaCland PEG 6000 treatments also up-regulate its expression in the shoot tip.Particularly,PEG6000 treatment significantly up-regulated its expression in the mature leaves.Five phytopathogenic fungal strains all significantly up-regulated its expression in the roots for 48 h after the inoculation.Among these pathogenic fungi,Rhizoctonia solani significantly up-regulated the expression of PdPapHSF-A4b in mature leaves.Cytospora chrysosporium down-regulated its expression in the shoot tip.After the induction by hormones for 48 h,ABA(100μM)induced significant up-regulation of the expression of PdPapHSF-A4b in the shoot tips,mature leaves and the roots;JA(100μM)and SA(100μM)induced up-regulation of PdPapHSF-A4b the expression levels were significantly up-regulated in roots and down-regulated in leaves,but not in shoot tips.The results show that PdPapHSF-A4b participates in regulating plant resistance and the signaling pathways of phytohormones.