Toll and Imd pathways in Spodoptera frugiperda (Lep.: Noctuidae) cells are induced following Autographa californica (Lep.: Noctuidae) multiple nucleopolyhedrovirus infection
پذیرفته شده برای پوستر
عنوان دوره: سومین کنگره بین المللی حشره شناسی ایران
نویسندگان
Department of Entomology, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran,
چکیده
Baculoviruses are important invertebrate viruses and some of these viruses have been developed to microbial insecticides, particularly against lepidopterans. Autographa californica multiple nucleopolyhedrovirus (AcMNPV) is the type species of family Baculoviridae that have large circular, double-stranded DNA genomes. In the present study we determined the role of Toll and Imd pathways, which are two of most important innate immune response pathways, in Spodoptera frugiperda (Sf9) cells after AcMNPV infection. Toll and Imd pathways are known as antibacterial and antifungal immune response in insects, respectively, however, recent studies have suggested that theses pathways may also be involved in antiviral response. We considered mRNAs from ESTs and transcriptome sequences extracted from the National Centre for Biotechnology Information (NCBI) to identify and characterize Imd pathway core genes (i.e. Imd and Relish) and Toll pathway core genes (e.g. Spatzle and dorsal) in S. frugiperda. Five antimicrobial peptides genes (AMP) including Gloverin, Galliomicin, Gallerimycin, Cecropin and Transferrin were also identified and selected for future investigation. Specific Primers were designed using primer3plus and oligo7 softwares. To determine the transcription response of these genes following AcMNPV infection, the Sf9 cells were transferred to a 12 well plate and infected with 200 µl of AcMNPV (MOI of 5). RNA samples were extracted from the mock and infected cells at 4, 8, 16, 24 and 48 h post infection (hpi) followed by cDNA synthesis using oligo dT primer. QPCRs were performed using cDNA samples and specific primers to the genes. Our results showed that the expression level of Imd (receptor of Imd pathway), Relish (transcription factor of Imd pathway) and dorsal (transcription factor of toll pathway) were up-regulated after 24 hpi while mRNA level of Spt (receptor of Toll pathway) was down regulated after 24 hpi. These results indicated that both pathway induced following AcMNPV infection. We also assessed that gene expression levels of different AMPs and found that the expression level of cecropin was up-regulated at 8 and 16 hpi followed by down regulation at 24 and 48 hpi. The expression levels of galliomicin and trancferin were increased at 48 hpi and the expression of gloverin and gallerimycin remained unchanged. These results showed that some of the AMPs also respond to AcMNPV infection. Together, our results suggest that Imd and Toll pathways in Sf9 cells are induced by AcMNPV infection that result in induction of some AMPs in these cells that merit more functional investigations.
کلیدواژه ها