title: Generation of a Transcriptome in a Model Lepidopteran Pest, Heliothis virescens, Using Multiple Sequencing Strategies for Profiling Midgut Gene Expression.
abstract: Heliothine pests such as the tobacco budworm, Heliothis virescens (F.), pose a significant threat to production of a variety of crops and ornamental plants and are models for developmental and physiological studies. The efforts to develop new control measures for H. virescens, as well as its use as a relevant biological model, are hampered by a lack of molecular resources. The present work demonstrates the utility of next-generation sequencing technologies for rapid molecular resource generation from this species for which lacks a sequenced genome. In order to amass a de novo transcriptome for this moth, transcript sequences generated from Illumina, Roche 454, and Sanger sequencing platforms were merged into a single de novo transcriptome assembly. This pooling strategy allowed a thorough sampling of transcripts produced under diverse environmental conditions, developmental stages, tissues, and infections with entomopathogens used for biological control, to provide the most complete transcriptome to date for this species. Over 138 million reads from the three platforms were assembled into the final set of 63,648 contigs. Of these, 29,978 had significant BLAST scores indicating orthologous relationships to transcripts of other insect species, with the top-hit species being the monarch butterfly (Danaus plexippus) and silkworm (Bombyx mori). Among identified H. virescens orthologs were immune effectors, signal transduction pathways, olfactory receptors, hormone biosynthetic pathways, peptide hormones and their receptors, digestive enzymes, and insecticide resistance enzymes. As an example, we demonstrate the utility of this transcriptomic resource to study gene expression profiling of larval midguts and detect transcripts of putative Bacillus thuringiensis (Bt) Cry toxin receptors. The substantial molecular resources described in this study will facilitate development of H. virescens as a relevant biological model for functional genomics and for new biological experimentation needed to develop efficient control efforts for this and related Noctuid pest moths.
authors.affiliation: Southern Insect Management Research Unit, USDA, Agricultural Research Service, Stoneville, MS, 38776, United States of America.
authors.forename: Omaththage P
authors.initials: OP
authors.lastname: Perera
authors.affiliation: Biological Control of Insects Research Laboratory, USDA, Agricultural Research Service, Columbia, Missouri, 65203, United States of America.
authors.forename: Kent S
authors.initials: KS
authors.lastname: Shelby
authors.affiliation: Biological Control of Insects Research Laboratory, USDA, Agricultural Research Service, Columbia, Missouri, 65203, United States of America.
authors.forename: Holly J R
authors.initials: HJ
authors.lastname: Popham
authors.affiliation: Dept. Entomology, North Carolina State University, Raleigh, NC, 27607, United States of America.
authors.forename: Fred
authors.initials: F
authors.lastname: Gould
authors.affiliation: Dept. Entomology, University of Georgia, Athens, GA, 30602, United States of America.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Adang
authors.affiliation: Dept. Entomology and Plant Pathology, University of Tennessee, Knoxville, TN, 37996, United States of America.
authors.forename: Juan Luis
authors.initials: JL
authors.lastname: Jurat-Fuentes
mesh_terms: D000469:Alkaline Phosphatase / Q000235:genetics / Q000378:metabolism; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D003062:Codon; D020451:Contig Mapping; D004064:Digestive System / Q000378:metabolism*; D020869:Gene Expression Profiling; D016678:Genome; D006434:Hemocytes / Q000378:metabolism; D059014:High-Throughput Nucleotide Sequencing; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism; D007814:Larva / Q000235:genetics / Q000378:metabolism; D009036:Moths / Q000145:classification / Q000235:genetics* / Q000254:growth & development; D010802:Phylogeny; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism; D017423:Sequence Analysis, RNA; D059467:Transcriptome
chemical_list: D001426:Bacterial Proteins; D003062:Codon; C095416:Cry toxin receptors; D019476:Insect Proteins; D034741:RNA, Small Interfering; D011956:Receptors, Cell Surface; D000469:Alkaline Phosphatase