Analysis of genes expression of Spodoptera exigua larvae upon AcMNPV infection

• Published in: PloS one Vol. 7; no. 7; p. e42462
• Main Authors: Choi, Jae Young, Roh, Jong Yul, Wang, Yong, Zhen, Zou, Tao, Xue Ying, Lee, Joo Hyun, Liu, Qin, Kim, Jae Su, Shin, Sang Woon, Je, Yeon Ho
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 31.07.2012; Public Library of Science (PLoS)
• Subjects: Agricultural biotechnology; Agriculture; Animal vaccines; Animals; Antimicrobial peptides; Apoptosis; Autographa californica; Binding proteins; Biology; Deoxyribonucleic acid; DNA; DNA, Complementary; Drosophila; Gene expression; Gene Expression Profiling; Gene sequencing; Genes; Genomes; Genomic libraries; Health aspects; Infection; Infections; Insecticides; Insects; Isoforms; Juvenile hormones; Larva - growth & development; Larva - virology; Larvae; Lepidoptera; Life sciences; Morphology; Noctuidae; Nucleopolyhedrovirus - pathogenicity; Peptides; Protein binding; Protein expression; Proteins; Ribonucleic acid; RNA; Spodoptera - genetics; Spodoptera - virology; Spodoptera exigua; Spodoptera frugiperda; Topical application; Transcriptome; Viral infections; Virus diseases; Viruses; California
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0042462

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. 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. 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.