Genetic Engineering of Baculoviruses

Baculoviruses are arthropod‐specific, enveloped viruses with circular, supercoiled double‐ stranded DNA genomes [1]. They infect Lepidoptera (butterflies and moths), Hymenoptera (sawflies) and Diptera (mosquitoes) [2]. While many viruses are studied because of their damaging effects, the study of baculoviruses was stimulated by their potential utility to control insect pests [3]. Later, the utility of baculovirus as gene expression vectors was evidenced and a new research area emerged [4]. A major step forward was the development of bacmid technology [5] (the construction of bacterial artificial chromosomes containing the genome of the baculovirus) which allows the manipulation of the baculovirus genome in bacteria. With this technology, foreign genes can be introduced into the bacmid by site‐ directed recombina‐ tion or by transposition. Baculoviruses have been used to explore fundamental questions in molecular biology such as the nature of programmed cell‐death [6]. Moreover, the ability of baculoviruses to transduce mammalian cells led to the consideration of their use as gene therapy and vaccine vectors. Strategies for genetic engineering of baculoviruses have been developed to meet the requirements of new application areas, and the establishment of new genetic modification systems is still necessary when an unexplored experimental system is to be addressed. The aim of this chapter is to detail the areas of application of the baculovirus in basic molecular biology and applied biotechnology and the strategies used to generate genetically modified baculoviruses according to each area of study.