Baculoviruses

Abstract Baculoviruses are large, complex deoxyribonucleic acid (DNA) viruses that infect arthropods. The viruses are highly pathogenic and a few members have been successfully exploited as biological control agents for agricultural and forestry pests. With the exception of a virus pathogenic to silk moths ( Bombyx mori nucleopolyhedrovirus (NPV)), most baculovirus research is geared towards increasing virulence. The type species of baculoviruses, Autographa californica NPV, is widely used as a eukaryotic expression system for the production of vaccines and other proteins of medical and biological importance. Baculoviruses are also good model systems for the study of apoptosis, DNA replication, transcription, pathogenesis, membrane fusion and virus infectivity. Key Concepts: Baculoviruses are rod‐shaped, enveloped viruses of 30–60 nm in diameter and 250–300 nm in length. Baculoviruses infect insects of the orders Lepidoptera, Diptera and Hymenoptera. Baculoviruses have been genetically engineered to be highly efficient eukaryotic expression systems. Baculoviruses are unusual in making two different infectious forms: occluded virus for spreading infection from insect to insect and budded virus for spreading of viral infection within an infected insect. Baculoviruses have circular‐double stranded genomes, ranging from 80 to 180 kb. Baculoviruses use actin filaments for intracellular transport. Baculovirus DNA is infectious. Baculoviruses use host RNA polymerase for synthesis of early genes and encode a viral RNA polymerase for transcription of late genes. Baculovirus infection spreads through the tracheal system. Baculoviruses have been successfully used to control insect pests.