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Cellosaurus publication CLPUB00722

Publication number CLPUB00722
Authors Hepat R.P., Erlandson M.A., Harrison R.L., Willis L.G., Theilmann D.A.
Title Role of Plutella xylostella nucleopolyhedrovirus-CL3 ie2 in host range adaptation.
Citation (In) 50th annual meeting and golden jubilee celebration of the Society for Invertebrate Pathology; pp.11-11; San Diego (2017)
Web pages http://www.sipweb.org/docs/SIP%202017_Complete%20Program.pdf
Abstract The diamondback moth (Plutella xylostella) is one of the most important destructive insect pests of cruciferous crops worldwide. Previous studies identified both alpha-and betabaculoviruses that can infect and kill this important lepidopteran pest. The genome of the alphabaculovirus isolate Plutella xylostella nucleopolyhedrovirus-CL3 (PlxyNPV-CL3) was recently sequenced and was found to be nearly identical (98.5%) to the genome of Autographa californica multiple nucleopolyhedrovirus (AcMNPV). Interestingly PlxyNPV-CL3 is highly lethal for P. xylostella, whereas AcMNPV is not. Therefore, any differences in the genome of these two viruses may identify genes that are required for host adaptation. The dominant difference between the PlxyNPV-CL3 and AcMNPV-C6 genome is the open reading frame of the ie2 gene. The predicted amino acid sequences of the two IE2 proteins exhibit only 37.5% similarity. To determine if PlxyNPV-CL3 IE2 is responsible for adaptation of AcMNPV to P. xylostella, recombinant viruses were generated using bacmids. These viruses were an ie2 knockout (vie2KO), and the ie2 knockout repaired with AcMNPV or PlxyNPV-CL3 ie2 tagged with HA epitope (vie2KO-acie2HA and vie2KO-pxie2HA respectively). Each of these viruses was tested for replication in various cell lines which including Sf9, Tn5b1-4, and PxE-Po#583. Previous studies have not analyzed the impact of a complete AcMNPV ie2 knockout. Surprisingly, our results showed that deletion of ie2 led to a greater than 90% reduction in budded virus (BV) production compared to wildtype virus. In addition, occlusion body (OB) production was also greatly reduced. Initial results with vie2KO-pxie2HA indicate that PlxyNPV-CL3 IE2 can rescue vie2KO producing BV titers nearly as high as AcMNPV IE2. Further studies analyzing virus infection in P. xylotella larvae will be reported.
Cell lines CVCL_C2VX; PxE-Po#583