@article {465,
	title = {Impact of a basement membrane-degrading protease on dissemination and secondary infection of Autographa californica multiple nucleopolyhedrovirus in Heliothis virescens (Fabricus)},
	volume = {88},
	year = {Submitted},
	note = {08-10-200906-02-2012NormalDepartment of Entomology, Iowa State University, Ames, IA 50011, USA.enghttp://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve\&db=pubmed\&dopt=Abstract\&list_uids=17374754},
	pages = {1109 - 1119},
	abstract = {ScathL is a cathepsin L-like cysteine protease from the flesh fly, Sarcophaga peregrina, that digests components of the basement membrane (BM) during insect metamorphosis. A recombinant baculovirus that expresses ScathL (AcMLF9.ScathL) kills larvae of the tobacco budworm, Heliothis virescens, significantly faster than the wild-type virus and triggers melanization and tissue fragmentation in infected larvae shortly before death. As BMs are a potential barrier to the spread of baculovirus secondary infection to other tissues in the host, this study tested the hypothesis that the rapid death of insects infected with AcMLF9.ScathL was caused by accelerated secondary infection resulting from the degradation of host BMs by ScathL. Viruses expressing catalytically active or inactive ScathL were used to examine the effects of ScathL activity on budded virus release into the haemocoel during infection, the production of polyhedra in infected larvae and the rate of infection of the gut, trachea, haemocytes, fat body and Malpighian tubules. It was concluded that the enhanced insecticidal efficacy of the recombinant baculovirus that expresses ScathL does not result from altered tissue tropism or accelerated systemic infection. Implications for the role of the BM as a barrier to baculovirus dissemination within the host insect are discussed.},
	keywords = {Animals, Basement Membrane/*metabolism, Cathepsins/*metabolism, Cysteine Endopeptidases/*metabolism, Digestive System/virology, Fat Body/virology, Hemocytes/virology, Hemolymph/virology, Larva/virology, Malpighian Tubules/virology, Moths/*virology, Nucleopolyhedrovirus/enzymology/genetics/pathogenicity/*physiology, Trachea/virology},
	author = {Li, H. and Tang, H. and Harrison, R. L. and Bonning, B. C.}
}
@article {471,
	title = {Tissue specificity of a baculovirus-expressed, basement membrane-degrading protease in larvae of Heliothis virescens},
	volume = {39},
	year = {Submitted},
	note = {08-10-200906-02-2012NormalDepartment of Entomology, Iowa State University, 418 Science II, Ames, IA 50011-3222, USA.enghttp://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve\&db=pubmed\&dopt=Abstract\&list_uids=17959212},
	pages = {431 - 443},
	abstract = {ScathL is a cathepsin L-like cysteine protease from the flesh fly, Sarcophaga peregrina, which digests components of the basement membrane during insect metamorphosis. A recombinant baculovirus (AcMLF9.ScathL) expressing ScathL kills larvae of the tobacco budworm Heliothis virescens significantly faster than the wild type virus and triggers melanization and tissue fragmentation shortly before death. The tissue fragmentation was assumed to be a direct consequence of basement membrane degradation by ScathL. The goal of this study was to investigate the tissue specificity of ScathL when expressed by AcMLF9.ScathL using light, transmission and scanning electron microscopy. Baculovirus expression of ScathL resulted in damage to the basement membrane overlying the midgut, fat body and muscle fibers in larvae infected with AcMLF9.ScathL, but not in larvae infected with the control virus AcMLF9.ScathL.C146A or wild type virus AcMNPV C6. Injection of recombinant ScathL and high levels of baculovirus-mediated expression of ScathL resulted in complete loss of the gut. Extensive damage to the basement membrane mediated by ScathL likely resulted in loss of viability of the underlying tissue and subsequent death of the insect. These results confirm the conclusion of an earlier study (Philip, J.M.D., Fitches, E., Harrison, R.L., Bonning, B.C., Gatehouse, J.A., 2007. Characterisation of functional and insecticidal properties of a recombinant cathepsin L-like proteinase from flesh fly (Sarcophaga peregrina), which plays a role in differentiation of imaginal discs. Insect Biochem. Mol. Biol. 37, 589-600) of the remarkable specificity of this protease.},
	keywords = {Animals, Baculoviridae/*genetics, Basement Membrane/*metabolism/ultrastructure, development/*metabolism/ultrastructure, Digestive System/cytology/metabolism/ultrastructure, Endopeptidases/*genetics/*metabolism, Fat Body/cytology/metabolism/ultrastructure, Insecticides/*metabolism, Larva/cytology/metabolism/ultrastructure, Lepidoptera/cytology/*growth \&amp, Organ Specificity},
	author = {Tang, H. and Li, H. and Lei, S. M. and Harrison, R. L. and Bonning, B. C.}
}
@article {365,
	title = {Insecticidal activity of a basement membrane-degrading protease against Heliothis virescens (Fabricius) and Acyrthosiphon pisum (Harris)},
	volume = {54},
	year = {Submitted},
	note = {08-10-200906-02-2012NormalDepartment of Entomology, Iowa State University, 418 Science II, Ames, IA 50011-3222, USA.enghttp://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve\&db=pubmed\&dopt=Abstract\&list_uids=18395222},
	pages = {777 - 789},
	abstract = {ScathL is a cathepsin L-like cysteine protease derived from the flesh fly Sarcophaga peregrina that functions in basement membrane (BM) remodeling during insect development. A recombinant baculovirus expressing ScathL (AcMLF9.ScathL) kills larvae of the tobacco budworm, Heliothis virescens, significantly faster than the wild-type virus. Here, we show that the occurrence of larval melanization prior to death was closely associated with the onset of high cysteine protease activity of ScathL in the hemolymph of fifth instars infected with AcMLF9.ScathL, but not with AcMLF9.ScathL.C146A, a recombinant baculovirus expressing a catalytic site mutant of ScathL. Fragmented fat body, ruptured gut and malpighian tubules, and melanized tracheae were observed in AcMLF9.ScathL-infected larvae. Phenoloxidase activity in hemolymph was unchanged, but the pool of prophenoloxidase was significantly reduced in virus-infected larvae and further reduced in AcMLF9.ScathL-infected larvae. The median lethal dose (LD(50)) for purified ScathL injected into fifth-instar H. virescens was 11.0 microg/larva. ScathL was also lethal to adult pea aphids, Acyrthosiphon pisum with a similar loss of integrity of the gut and fat body. Injection with purified ScathL.C146A or bovine trypsin at 20 microg/larva did not produce any effect in either insect. These results illustrate the potent insecticidal effects of ScathL cysteine protease activity and the potential for use of ScathL in development of insect resistant transgenic plants when combined with an appropriate delivery system.},
	keywords = {Animals, Baculoviridae, Basement Membrane/*drug effects, Biological Assay, Catechol Oxidase/blood, Cathepsins/genetics/*toxicity, Cysteine Endopeptidases/genetics/*toxicity, Diptera/chemistry, Enzyme Precursors/blood, Hemiptera/*drug effects, Insecticides/*toxicity, Larva/drug effects/metabolism, Lethal Dose 50, Moths/*drug effects/metabolism},
	author = {Li, H. and Tang, H. and Sivakumar, S. and Philip, J. and Harrison, R. L. and Gatehouse, J. A. and Bonning, B. C.}
}
