四纹豆象Toll与抗菌肽基因对种群密度的响应  

Response of Expression Level of Tolls and Antimicrobial Peptides Genes to Population Density in Bean Beetle

作　　者：陈千权 王野影 CHEN Qianquan;WANG Yeying(School of Life Sciences,Guizhou Normal University,Guian 550025,China)

机构地区：[1]贵州师范大学生命科学学院

出　　处：《河南农业科学》2019年第9期90-97,共8页Journal of Henan Agricultural Sciences

基　　金：贵州省科学技术厅-贵州师范大学联合基金项目(黔科合LH字[2017]7375号);贵州师范大学博士启动基金项目(11904/0517070)

摘　　要：为揭示四纹豆象(Callosobruchus maculatus)免疫信号转导与抗菌肽基因表达量对种群密度的响应机制,利用tBLASTn在四纹豆象腹部转录组数据中鉴定Toll、IMD(Immune deficiency)及抗菌肽基因,并以FPKM值指示基因表达量。结果表明,从腹部转录组中鉴定到6个富含亮氨酸结构域的Toll信号通路受体基因,其中,Toll-1进化速率较快,Toll-3、Toll-10、Toll-7、Toll-8、Toll-6进化速率依次降低。鉴定到IMD信号通路的胞内关键信号分子基因IMD和受体肽聚糖识别蛋白LC基因(Peptidoglycan recognition protein LC,PGRP-LC)。IMD和PGRP-LC的进化速率与Toll-3相似。表达量方面,Toll-1表达量最低,其FPKM值为0.32,且种群密度对其表达量无显著影响,Toll-3、Toll-6、Toll-7、Toll-8、Toll-10的表达量在高密度群体中显著或极显著上调,其中,Toll-7表达量最高,其在高密度群体、低密度群体中的FPKM值分别为127.25、57.92。种群密度对IMD和PGRP-LC的表达量无显著影响。鉴定到7个抗菌肽基因,即1个Defensin(防御素基因)、1个Cecropin(天蚕素基因)、2个Apidaecin(蜜蜂抗菌肽基因)、3个Drosomycin(抗真菌肽基因),其中,Drosomycin在进化方面最保守。Apidaecin-1表达量最低,其FPKM值为6.58,Defensin表达量最高,高密度群体、低密度群体的FPKM值分别为1 277.23、683.87。种群密度对Apidaecin-1、Cecropin、Apidaecin-2的表达量无显著影响,Defensin和3个Drosomycin在高密度群体中上调。综上所述,Toll-3、Toll-6、Toll-7、Toll-8、Toll-10与Defensin、Drosomycin-1、Drosomycin-2、Drosomycin-3在高种群密度条件下上调表达。In order to unveil the response mechanism of genes related to immunity signal transduction and antimicrobial peptide to population density,tBLASTn was used to identify genes related to Toll,IMD(Immune deficiency)and antimicrobial peptide genes from RNA-sequencing data of bean beetle(Callosobruchus maculatus).FPKM(Fragments per kilobase per million mapped reads)value was used to measure the expression level of these genes.The results showed that six Toll signaling pathway receptor genes which encoded proteins containing leucine-rich repeats domains were identified.Toll-1 had the fastest evolutionary rate,while the evolutionary rates of Toll-3,Toll-10,Toll-7,Toll-8 and Toll-6 decreased in turn.IMD,an intracellular key signal gene,and Peptidoglycan recognition protein LC(PGRP-LC),a receptor gene of IMD signaling pathway,were identified.IMD and PGRP-LC had similar evolutionary rate to Toll-3.At expression level,Toll-1 was the lowest(FPKM=0.32),and was not regulated by population density.The expression levels of Toll-3,Toll-6,Toll-7,Toll-8,and Toll-10 were significantly or extremely significantly up-regulated in high-density individuals,with Toll-7 having the highest expression level(its FPKMs in high-density individuals and low-density individuals were 127.25 and 57.92,respectively).Population density had no significant effect on the expression level of IMD and PGRP-LC.Seven antibacterial peptide genes were identified,including one Defensin(defensin gene),one Cecropin(cetanin gene),two Apidaecins(bee antibacterial peptide genes),and three Drosomycins(anti-fungal peptide genes).Among them,Drosomycin was the most conservative one in evolution.Antibacterial peptide Apidaecin-1 had the lowest expression level(FPKM=6.58)and Defensin had the highest expression level(its FPKMs in high-density individuals and low-density individuals were 1 277.23 and 683.87,respectively).Population density had no significant effect on the expression level of Apidaecin-1,Cecropin and Apidaecin-2.Defensin and three Drosomycin genes were up-reg

关 键 词：四纹豆象 种群密度 免疫信号转导相关基因 抗菌肽 TOLL IMD 

分 类 号：S433.4[农业科学—农业昆虫与害虫防治]