5’ UTR studies of the AgMNPV ie-1 gene

BILEN, M.F.; NEVES, S.G.; RIBEIRO, B.M.; LOZANO, M.E.; GHIRINGHELLI, P.D.

Salvador de Bahía, Brasil

Congreso; XVI Encontro Nacional de Virología; 2005

Sociedad Brasilera de Virologia

Baculoviruses belong to a family of viral pathogens which infects arthropods, in particular, lepidopteran insects. Baculoviruses have attracted attention due to their use as biological control agents of agricultural pests and as eukaryotic expression system for heterologous gene expression. Anticarsia gemmatalis multipe nucleopolyhedrovirus (AgMNPV) is the world most used viral biological control agent to date. This virus is used in more than two million hec of soybean crops each year in Latin America for the control of the soybean pest, A. gemmatalis. Several studies with different baculoviruses showed that the IE-1 protein has an essential role in the viral cycle, being important in transcriptional regulation of several genes (early and late). Besides, it is also important for viral replication. In order to get more information on the regulation of the AgMNPV viral cycle, the role of the IE-1 protein in this process and the transcriptional regulation of this gene, we have carried out sequence analysis of the ie-1 gene and found potential regulatory motifs in it`s 5´ UTR. Furthermore, we constructed different versions of the 5´ UTR of the ie-1 promoter fused with two reporter genes (b-galactosidase and fire-fly luciferase). Through transient assays with the different promoter constructs fused with the reporter genes, we were able to check the role of different promoter regions quantifying the activity of the reporter proteins expressed. In order to determine the influence of the viral context on the ie-1 transcriptional regulation, we have constructed a recombinant AgMNPV containing the 5´ and 3´ UTR regions of the ie-1 gene fused to the b-galactosidase gene in the polyhedrin locus and analysed the expression of the reporter protein at different times post-infection.