title: Transcriptome analysis of the brown planthopper Nilaparvata lugens.
abstract: BACKGROUND
  The brown planthopper (BPH) Nilaparvata lugens (Stål) is one of the most serious insect pests of rice in Asia. However, little is known about the mechanisms responsible for the development, wing dimorphism and sex difference in this species. Genomic information for BPH is currently unavailable, and, therefore, transcriptome and expression profiling data for this species are needed as an important resource to better understand the biological mechanisms of BPH.
  
  
  RESULTS
  In this study, we performed de novo transcriptome assembly and gene expression analysis using short-read sequencing technology (Illumina) combined with a tag-based digital gene expression (DGE) system. The transcriptome analysis assembles the gene information for different developmental stages, sexes and wing forms of BPH. In addition, we constructed six DGE libraries: eggs, second instar nymphs, fifth instar nymphs, brachypterous female adults, macropterous female adults and macropterous male adults. Illumina sequencing revealed 85,526 unigenes, including 13,102 clusters and 72,424 singletons. Transcriptome sequences larger than 350 bp were subjected to Gene Orthology (GO) and KEGG Orthology (KO) annotations. To analyze the DGE profiling, we mainly compared the gene expression variations between eggs and second instar nymphs; second and fifth instar nymphs; fifth instar nymphs and three types of adults; brachypterous and macropterous female adults as well as macropterous female and male adults. Thousands of genes showed significantly different expression levels based on the various comparisons. And we randomly selected some genes to confirm their altered expression levels by quantitative real-time PCR (qRT-PCR).
  
  
  CONCLUSIONS
  The obtained BPH transcriptome and DGE profiling data provide comprehensive gene expression information at the transcriptional level that could facilitate our understanding of the molecular mechanisms from various physiological aspects including development, wing dimorphism and sex difference in BPH.
authors.affiliation: Key Laboratory of Molecular Biology of Crop Pathogens and Insects of Ministry of Agriculture, Institute of Insect Science, Zhejiang University, Hangzhou, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Xue
authors.forename: Yan-Yuan
authors.initials: YY
authors.lastname: Bao
authors.forename: Bao-Ling
authors.initials: BL
authors.lastname: Li
authors.forename: Yan-Bing
authors.initials: YB
authors.lastname: Cheng
authors.forename: Zhi-Yu
authors.initials: ZY
authors.lastname: Peng
authors.forename: Hang
authors.initials: H
authors.lastname: Liu
authors.forename: Hai-Jun
authors.initials: HJ
authors.lastname: Xu
authors.forename: Zeng-Rong
authors.initials: ZR
authors.lastname: Zhu
authors.forename: Yong-Gen
authors.initials: YG
authors.lastname: Lou
authors.forename: Jia-An
authors.initials: JA
authors.lastname: Cheng
authors.forename: Chuan-Xi
authors.initials: CX
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002874:Chromosome Mapping; D005260:Female; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D015723:Gene Library; D014644:Genetic Variation; D006430:Hemiptera / Q000235:genetics* / Q000378:metabolism*; D008297:Male; D008954:Models, Biological; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D015398:Signal Transduction; D014158:Transcription, Genetic