Molecular characterization and genetic organization of the inhibitor of apoptosis gene (iap-5) region of the Pieris rapae granulovirus.

Pieris rapae granulovirus (PiraGV) is a baculovirus pathogenic to the insect P. rapae (Pieridae, Lepidoptera). Though being known for decades, information on the genetic organization of this virus remains limited. In an effort to characterize this virus, an 11.8 kb BamHI restriction fragment that harbors the inhibitor of apoptosis gene (iap-5) was sequenced. Our results indicate that this region contains important genes such as dnapol, lef-3, lef-9, and dnaligase that are involved in transcription and replication of the virus. The gene content and synteny in this region are highly conserved among granulovirus genomes. Phylogenetic analysis showed that PiraGV genes are more closely related to the Choristoneura occidentalis granulovirus (ChocGV) than other characterized granulovirus (GVs).