Construction and characterization of a recombinant insect iridovirus

Chilo iridescent virus (CIV) is an insect virus belongs to the Iridoviridae family and has wide host spectrum among pest insects. Sequence analysis of the DNA genome was carried out and length of the genome was determined as 212,482 base pair. CIV was able to be adapted to the cell culture and determined to be replicated in a number of cell strains though at low levels. For placing a foreign gene into virus genome a suitable place should be opened means a gene or region must be deleted from the genome. However deleting a gene from the genome should not effect the viral replication or any other mechanism of the virus. Based on bioinformatics analysis, ORF 157 was determined to be non-functional although it exist among apoptosis inhibitor gene. In this thesis, construction and characterization of a recombinant insect iridovirus is generated first time. This recombinant (rCIVΔ157L-gfp) generated by homologous recombination in cell culture successfully expressed the reporter gene gfp (green fluorescent protein gene) under control of the CIV mcp promoter at the 157L locus. This study also showed that virus replication was not affected by replacing the 157L gene with gfp. Virus replication and production during rCIVΔ157L-gfp infection was similar to that of wt-CIV. Consequently, it can be said that the CIV 157L locus can be used as a site for insertion of foreign DNAs for insect biocontrol and biotechnological.