大灰象甲非典型气味受体基因SvelOrco的克隆及组织表达谱分析

旨在克隆大灰象甲Sympiezomias velatus的Orco基因,明确其分子特征及其组织表达谱。通过分析成虫触角转录组数据并利用RT-PCR克隆出大灰象甲Orco基因,对大灰象甲Orco蛋白进行结构分析和系统发育分析,并采用qPCR测定Orco基因在大灰象甲成虫不同组织中的表达量。克隆获得大灰象甲Orco基因并命名为SvelOrco(GenBank登录号：OM417062),其开放阅读框长1 449 bp,编码482个氨基酸。预测SvelOrco蛋白的分子质量为53.49 ku,等电点为5.66,主要由α-螺旋和无规则卷曲组成,有7个跨膜结构域。系统发育分析表明大灰象甲与云杉八齿小蠹Ips typographus亲缘关系最近。qPCR结果显示：SvelOrco主要在大灰象甲成虫触角上表达,雄虫触角表达量最高,是雌虫触角表达量的1.22倍,SvelOrco在翅部也有少量表达,在头、胸、腹和足的表达量极低。

Gene Cloning and Tissue Expression Profiling of Odorant Rceptor Co-receptor in Sympiezomias velatus (Coleoptera:Curculionidae)

This study aims to clone the Orco gene from Sympiezomias velatus,anddetermine its molecular characteristics andtissue-specific expression profiles.UsingRT-PCR and antenna transcriptome data,Orcogene from S.velatus adultswas cloned.The structure and phylogenetic analysis of the Orco protein were performed.qPCR was used to determine the Orco gene expression level in different tissues of S.velatus adults.The cloned Orco gene of S.velatus was named as SvelOrco (GenBank accession number:OM417062) with an open reading frame of 1 449 bp encoding 482 amino acids.The predicted molecular weight of SvelOrco protein was 53.49 ku and the isoelectric point was 5.66.SvelOrco protein mainly consisted of alpha helices and random coils,and had seven transmembrane domains.The phylogenetic analysis suggested that S.velatus was closely related to Ips typographus.The qPCR results showed that SvelOrco was mainly expressed in the adult antennae of S.velatus.SvelOrcoexhibited the highest expression levelin male antennae,which was 1.22 fold as high as that in femaleantennae.A low expression level of SvelOrco was detected in the adult wings.The expression level of SvelOrco in heads,thorax,abdomen and legs of adults was negligible.