title: Analysis of genes expression of Spodoptera exigua larvae upon AcMNPV infection.
abstract: BACKGROUND
  The impact of Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) infection on host gene expression in Spodoptera exigua 4th instar larvae was investigated through the use of 454 sequencing-based RNA-seq of cDNA libraries developed from insects challenged with active AcMNPV or heat-inactivated AcMNPV.
  
  
  RESULTS
  By comparing the two cDNA libraries, we show that 201 host genes are significantly up-regulated and 234 genes are significantly down-regulated by active AcMNPV infection. Down-regulated host genes included genes encoding antimicrobial peptides, namely three gloverin isoforms and an attacin, indicating that the viral infection actively repressed the expression of a portion of the host immune gene repertoire. Another interesting group of down-regulated host genes included genes encoding two juvenile hormone binding proteins and a hexamerin, all of which are involved in juvenile hormone regulation. The expression of these genes was enhanced by the topical application of Juvenile Hormone III (JHIII) in the insects challenged with heat-inactivated AcMNPV. However, infection with the active virus strongly suppresses the expression of these three genes, regardless of the absence or presence of JHIII.
  
  
  CONCLUSIONS
  Using RNA-seq, we have identified groups of immune-regulated and juvenile hormone-regulated genes that are suppressed by infection with active AcMNPV. This information and further studies on the regulation of host gene expression by AcMNPV will provide the tools needed to enhance the utility of the virus as an effective protein expression system and as an insecticide.
authors.affiliation: Department of Agricultural Biotechnology, College of Agriculture and Life Science, Seoul National University, Seoul, Korea.
authors.forename: Jae Young
authors.initials: JY
authors.lastname: Choi
authors.forename: Jong Yul
authors.initials: JY
authors.lastname: Roh
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.forename: Zou
authors.initials: Z
authors.lastname: Zhen
authors.forename: Xue Ying
authors.initials: XY
authors.lastname: Tao
authors.forename: Joo Hyun
authors.initials: JH
authors.lastname: Lee
authors.forename: Qin
authors.initials: Q
authors.lastname: Liu
authors.forename: Jae Su
authors.initials: JS
authors.lastname: Kim
authors.forename: Sang Woon
authors.initials: SW
authors.lastname: Shin
authors.forename: Yeon Ho
authors.initials: YH
authors.lastname: Je
mesh_terms: D000818:Animals; D018076:DNA, Complementary; D020869:Gene Expression Profiling; D007814:Larva / Q000254:growth & development* / Q000821:virology; D017924:Nucleopolyhedroviruses / Q000472:pathogenicity*; D018411:Spodoptera / Q000235:genetics* / Q000821:virology; D059467:Transcriptome
chemical_list: D018076:DNA, Complementary