title: Comparative analysis of expression profiling of the trypsin and chymotrypsin genes from Lepidoptera species with different levels of sensitivity to soybean peptidase inhibitors.
abstract: Peptidase inhibitors (PIs) are essential proteins involved in plant resistance to herbivorous insects, yet many insect species are able to escape the negative effects of these molecules. We compared the effects of acute and chronic ingestion of soybean peptidase inhibitors (SPIs) on Spodoptera frugiperda and Diatraea saccharalis, two Lepidoptera species with different sensitivities to SPI ingestion. We analyzed the trypsin and chymotrypsin gene expression profiles in both species. Acute exposure of S. frugiperda to the inhibitors activated seven genes (SfChy5, SfChy9, SfChy19, SfChy22, SfTry6, SfTry8, and SfTry10), whereas chronic exposure activated 16 genes (SfChy2, SfChy4, SfChy5, SfChy8, SfChy9, SfChy11, SfChy12, SfChy15, SfChy17, SfChy21, SfChy22, SfTry6, SfTry8, SfTry9, SfTry10, and SfTry12). By contrast, the challenge of D. saccharalis with SPIs did not differentially induce the expression of trypsin- or chymotrypsin-encoding genes, with the exception of DsChy7. Bayesian phylogenetic analysis of S. frugiperda trypsin protein sequences revealed two gene clades: one composed of genes responsive to the SPIs and a second composed of the unresponsive genes. D. saccharalis trypsin proteins were clustered nearest to the S. frugiperda unresponsive genes. Overall, our findings support a hypothesized mechanism of resistance of Noctuidae moths to SPIs, involving gene number expansion of trypsin and chymotrypsin families and regulation of gene expression, which could also explain the variable susceptibility between S. frugiperda and D. saccharalis to these plant inhibitors.
authors.affiliation: Departamento de Genética, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Av. Pádua Dias, 11, 13400-918 Piracicaba, SP, Brazil.
authors.forename: Thais P
authors.initials: TP
authors.lastname: Souza
authors.affiliation: Departamento de Genética, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Av. Pádua Dias, 11, 13400-918 Piracicaba, SP, Brazil.
authors.forename: Renata O
authors.initials: RO
authors.lastname: Dias
authors.affiliation: Departamento de Genética, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Av. Pádua Dias, 11, 13400-918 Piracicaba, SP, Brazil.
authors.forename: Elaine C
authors.initials: EC
authors.lastname: Castelhano
authors.affiliation: Centro de Biologia Molecular e Engenharia Genética, Universidade Estadual de Campinas, Av. Cândido Rondon, 400, 13083-875 Campinas, SP, Brazil.
authors.forename: Marcelo M
authors.initials: MM
authors.lastname: Brandão
authors.affiliation: Departamento de Ciências Biológicas, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Av. Pádua Dias, 11, 13400-918 Piracicaba, SP, Brazil.
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Moura
authors.affiliation: Departamento de Genética, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Av. Pádua Dias, 11, 13400-918 Piracicaba, SP, Brazil. Electronic address: mdcsilva@usp.br.
authors.forename: Marcio C
authors.initials: MC
authors.lastname: Silva-Filho
mesh_terms: D000818:Animals; D002918:Chymotrypsin / Q000235:genetics*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D008958:Models, Molecular; D011480:Protease Inhibitors / Q000494:pharmacology*; D011487:Protein Conformation; D013025:Glycine max / Q000737:chemistry*; D013045:Species Specificity; D018411:Spodoptera / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics*; D014357:Trypsin / Q000737:chemistry / Q000235:genetics*
chemical_list: D011480:Protease Inhibitors; D002918:Chymotrypsin; D014357:Trypsin
keywords: Diatraea saccharalis; Plant peptidase inhibitor; Serine peptidase; Spodoptera frugiperda