Behaviour of two recombinant baculoviruses for peroxidase expression in Lepidoptera

ROMERO L.; TARGOVNIK A.; LEVIN G.; MIRANDA MV.; CASCONE O.

Córdoba, Argentina

Congreso; SAIB; 2008

Baculovirus-insect cell system is a popular choice for heterologous gene expression when a eukaryotic environment is required. Autographa californica multiple nucleopolyhedrovirus (AcMNPV) is by far the most widely used baculovirus expression vector. In this work two recombinant viruses were constructed in order to compare the performance of HRPC expression in Lepidopteran hosts. The first one (AcMNPVHRPC occ-) was conventionally formed by introducing the HRPC gene in locus polyhedrin. The second construction (AcMNPVHRPC occ+) was identical except for polyhedrin gene presence under p10 promoter. Spodoptera frugiperda larvae (approximately 200 mg each) were infected by intrahaemocoelical injection with 50 ml of 6.106 ufp.ml-1 of both viral suspensions. At different days post-infection (dpi) HRPC expression in haemolymph was measured by its enzyme activity. HRPC levels achieved with both type of virions were not significantly different at any dpi. Thus, polyhedrin gene presence under p10 promotor does not affect the HRPC expression. AcMNPVHRPC occ+ showed to be as effective as AcMNPVHRPC occ- with the great advantage of being suitable for oral infection of permissive lepidopteran species.