title: Improved insecticidal activity of a recombinant baculovirus expressing spider venom cyto-insectotoxin.
abstract: Baculoviruses have a long history of safe use as specific, environmentally friendly insecticides that provide alternatives to chemical pesticides for controlling insect pests. However, their use has been limited by several factors, particularly their slow pathogenicity. In this study, we constructed a recombinant Bombyx mori nucleopolyhedrovirus (BmNPV) and an Autographa californica multiple nucleopolyhedrovirus (AcMNPV) that expressed an insect-specific cyto-insectotoxin (Cit1a) from the venom of the central Asian spider Lachesana tarabaevi. Cit1a is a comparatively long linear cytolytic molecule that contains a predicted α-helix structure composed of two short membrane-acting antimicrobial peptides (MAMPs) that are joined together in a "head-to-tail" shape. Cit1a fused to polyhedrin gene (polh) (polh-cit1a) was expressed in the nuclei as polyhedra in silkworm larvae, Bm5 and Sf9 cells. An early death of Bm5 and Sf9 cells by recombinant BmNPV/Polh-Cit1a and AcMNPV/Polh-Cit1a was observed compared with control viruses that lacked the toxin gene. The infected cells showed a loss of cytoplasm, membrane integrity, and structural changes, suggesting that recombinant baculovirus-infected cells were killed by the necrosis caused by Cit1a. In addition, the BmNPV/Polh-Cit1a showed a significant reduction in the median lethal time (LT50) against silkworm larvae compared with those of control BmNPV that lacked the cit1a gene.
authors.affiliation: Laboratory of Biotechnology, Integrated Bioscience Section, Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan. panna_ali@yahoo.com.
authors.forename: M P
authors.initials: MP
authors.lastname: Ali
authors.affiliation: Laboratory of Biotechnology, Integrated Bioscience Section, Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan. kato.tatsuya@shizuoka.ac.jp.|Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan. kato.tatsuya@shizuoka.ac.jp.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Kato
authors.affiliation: Laboratory of Biotechnology, Integrated Bioscience Section, Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan. park.enoch@shizuoka.ac.jp.|Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan. park.enoch@shizuoka.ac.jp.
authors.forename: Enoch Y
authors.initials: EY
authors.lastname: Park
mesh_terms: D000818:Animals; D016367:Baculoviridae / Q000235:genetics* / Q000254:growth & development; D012831:Bombyx / Q000502:physiology / Q000821:virology; D016923:Cell Death; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D003603:Cytotoxins / Q000096:biosynthesis* / Q000235:genetics / Q000633:toxicity*; D005822:Genetic Vectors; D007313:Insecta; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000633:toxicity*; D013111:Spider Venoms; D016019:Survival Analysis; D013997:Time Factors
chemical_list: D003603:Cytotoxins; D011993:Recombinant Fusion Proteins; D013111:Spider Venoms
keywords: Bombyx mori; Cyto-insectotoxin; Cytotoxicity; Pathogenicity; Recombinant baculovirus