香梨优斑螟EPSXL基因生物信息学及表达分析

Bioinformatics and Expression Analysis of EPSXL Gene of Euzophera pyriella

决定香梨优斑螟性别的基因尚不清楚,推测香梨优斑螟Sex-lethal(EPSXL)基因是潜在的主要性别决定基因,拟研究其在雌、雄个体不同组织及发育时期的表达。利用生物信息学软件预测香梨优斑螟EPSXL基因的氨基酸序列、分析蛋白质特性和构建近缘物种进化树,并采用荧光定量PCR技术检测该基因在头、胸、腹、翅中的表达情况。发现EPSXL基因编码区长度为1005 bp,编码334个氨基酸,具有2个保守的RRM结构域。其蛋白为碱性亲水性蛋白质,二级结构以α螺旋和无规则卷曲为主,有51个磷酸化位点和2个N-糖基化位点,不存在跨膜结构及信号肽。对比发现,EPSXL氨基酸序列与脐橙螟ATSXL的序列相似性最高。在雄性香梨优斑螟中EPSXL在成虫期和蛹期中mRNA表达量较高,在雌性中则在1龄和3龄幼虫期中表达量较高,在雄性腹部和胸部中的表达量极显著高于雌性相应组织。EPSXL蛋白具有2个保守的功能结构域,该基因mRNA表达在不同性别与组织间差异明显,能够为深入研究其功能提供理论依据。

The gene that determines the sex of Euzophera pyriella is still unclear.It is speculated that the Sex-lethal(EPSXL)gene of E.pyriella is a potential major sex-determining gene.This research aims to study its expression in different tissues and developmental stages of female and male individuals.Bioinformatics software was used to predict the amino acid sequence of EPSXL gene,to analyze the protein characteristics and construct the phylogenetic tree of its genetically close species.Quantitative PCR was applied to detect the expression of EPSXL gene in the head,thorax,abdomen and wing.It was found that the EPSXL gene coding region was 1005 bp in length,encoded 334 amino acids,and had 2 conserved RNA recognition motif(RRM)domains.The protein was a basic hydrophilic protein.The secondary structure was mainly constituted by alpha helix and random coils.There were 51 phosphorylated sites and 2 N-glycosylation sites,but no transmembrane structure and signal peptide.By comparison,it was found that the amino acid sequence of EPSXL had the highest similarity with the sequence of Amyelois transitella.The mRNA expression of EPSXL was higher in the adult and pupal of the male,while it was higher in the 1st and 3rd instar larvae of the female.The mRNA expressions of EPSXL in the abdomen and thorax of males were significantly higher than those in the female tissues.EPSXL protein has two conserved functional domains,and its mRNA expression differed obviously between gender and tissue,which can provide a theoretical basis for in-depth study of its function.