昆虫学报 ›› 2021, Vol. 64 ›› Issue (9): 1050-1060.doi: 10.16380/j.kcxb.2021.09.005

• 研究论文 • 上一篇    下一篇

中华按蚊含LY结构域的胰蛋白酶基因的分子特征及表达模式分析

张肖肖, 雷丹, 李香盈, 陈斌*   

  1.  (重庆师范大学昆虫与分子生物学研究所, 媒介昆虫重庆市重点实验室, 重庆 401331)
  • 出版日期:2021-09-20 发布日期:2021-09-03

Molecular characterization and expression profiling of LY domain-containing trypsin genes in Anopheles sinensis (Diptera: Culicidae)#br#

ZHANG Xiao-Xiao, LEI Dan, LI Xiang-Ying, CHEN Bin*   

  1. (Chongqing Key Laboratory of Vector Insects, Institute of Entomology and Molecular Biology, Chongqing Normal University, Chongqing 401331, China)
  • Online:2021-09-20 Published:2021-09-03

摘要:

【目的】在全基因组鉴定中华按蚊Anopheles sinensis 含LY结构域的胰蛋白酶(LY-trypsin)基因,探究其分子特征、表达模式以及系统发育关系。【方法】以NCBI数据库中冈比亚按蚊An. gambiae、埃及伊蚊Aedes aegypti、黑腹果蝇Drosophila melanogaster和致倦库蚊Culex quinquefasciatus胰蛋白酶家族基因的氨基酸序列为询问序列,通过本地Blast搜索鉴定中华按蚊基因组中胰蛋白酶基因,将中华按蚊LY-trypsin基因依据其结构域特征及系统发生关系进行命名LY-trypsin。运用生物信息学方法预测中华按蚊LY-trypsin基因的结构、在scaffold的定位、结构域、系统发育关系,及其在中华按蚊不同发育时期、成蚊不同组织和吸血前后雌成蚊中的表达模式。【结果】在中华按蚊全基因组上共鉴定得到27个中华按蚊LY-trypsin基因;在黑腹果蝇、冈比亚按蚊、致倦库蚊和埃及伊蚊基因组中未鉴定到LY-trypsin基因。中华按蚊27个LY-trypsin基因分别编码329~1 125个氨基酸,分子量在36.8~125.5 kD之间,等电点在4.73~8.94间。其中, 20个LY-trypsin具有信号肽,信号肽长度在10~62个氨基酸之间。这27个中华按蚊LY-trypsin基因的外显子数为1~5个,内含子长62~20 093 bp。这27个中华按蚊LY-trypsin基因被定位在11个scaffold上,其编码蛋白均有YWTD保守基序(LY基序);其中16个LY-trypsin基因所编码的氨基酸序列具有含丝氨酸、组氨酸和天冬氨酸催化三联体的活性位点。系统发育结果表明,27个中华按蚊LY-trypsin基因聚类为4个分支。在不同发育阶段,半数以上的中华按蚊LY-trypsin基因显示出相似的表达模式,在幼虫阶段均高水平表达;在中华按蚊不同成蚊组织中,LY-trypsin基因均有不同程度的表达;吸血前后雌蚊中仅有个别基因表达,并未发现表达特异性。【结论】本研究在中华按蚊基因组中首次鉴定出LYtrypsin基因,并揭示了这些LY-trypsin基因的分子特征和表达模式,为LY-trypsin基因的进一步研究提供了信息框架。

关键词: 中华按蚊, 胰蛋白酶基因, LY结构域, 基因组, 表达模式, 系统发育

Abstract: 【Aim】 To identify LY domain-containing trypsin (LY-trypsin) genes of Anopheles sinensis at the whole genome, and to explore their molecular characteristics, expression patterns and phylogentic relationships. 【Methods】 The amino acid sequences encoded by trypsin genes in An. gambiae, Aedes aegypti, Drosophila melanogaster, and Culex quinquefasciatus were downloaded from NCBI databases and used as queries to search for trypsin genes in An. sinensis genome using the local Blast program. LY-trypsin genes in An. sinensis were named based on domain characteristics and phylogenetic relationship. The structure, scaffold location, structural domain and phylogenetic relationships of LY-trypsin genes of An. sinensis, and their expression patterns at different developmental stages of An. sinensis, in different adult tissues of An. sinensis, and in female adults of An. sinensis before and after blood feeding were predicted using bioinformatics analysis. 【Results】 Twenty-seven LY-trypsin genes were identified in the whole genome of An. sinensis, while no LY-trypsin gene was identified in D. melanogaster, An. gambiae, C. quinquefasciatus, and A. aegypti. The 27 LY-trypsin genes of An. sinensis encode 329-1 125 amino acids, with the molecular weight of 36.8-125.5 kD, and pI of 4.73-8.94. Among them 20 LY-trypsin proteins have signal peptides, with their length ranging from 10 to 62 aa. The numbers of exons of the 27 LY-trypsin genes of An.sinensis range from one to five, and the length of introns ranges from 62 to 20 093 bp. The 27 LY-trypsin genes of An.sinensis are mapped on 11 scaffolds, their encoded proteins all have a conserved YWTD motif (LY motif), and the amino acid sequences encoded by 16 LY-trypsin genes of the 27 LY-trypsin genes have the active site containing the catalytic triad of serine, histidine and aspartic acid. Phylogenetic results showed that the 27 LY -trypsin genes of An. sinensis clustered into four branches. At different developmental stages, more than 50% of the LY-trypsin genes of An. sinensis showed similar expression patterns and were expressed at high levels during the larval stage. LY-trypsin genes were expressed in different adult tissues of An. sinensis. Only a few of LY-trypsin genes were expressed in female adults of An. sinensis before and after blood feeding without expression specificity. 【Conclusion】 In this study, LY-trypsin genes have been identified in the genome of An. sinensis for the first time, and the molecular characteristics and expression patterns of the LY-trypsin genes have been investigated. This study provides an information framework for the further study of LY-trypsin genes.

Key words: Anopheles sinensis, trypsin gene, LY domain, genome, expression pattern, phylogeny