title: Toxic effect of destruxin A on abnormal wing disc-like (SLAWD) in Spodoptera litura fabricius (Lepidoptera: Noctuidae).
abstract: BACKGROUND
  Destruxin A (DA) is a microbial insecticide with potent bioactivity against Spodoptera litura larvae. A previous proteomic analysis of S. litura (SL-1) cells exposed to DA showed the abnormal expression of wing disc-like protein of S. litura (SLAWD). To further understand the effect of DA on SLAWD expression, a functional study was carried out.
  
  
  RESULTS
  The SLAWD gene (SLAWD) was cloned and an open reading frame of 537 bp encoding a polypeptide of 178 amino acids was detected. Real-time fluorescence quantitative PCR (qRT-PCR) suggested that SLAWD is expressed in all developmental stages of S. litura, but expression was highest during the pupal and adult stages. RNAi knockdown of SLAWD expression in 6th-stage larvae was achieved by the microinjection of a specific double-stranded RNA (dsRNA). The results showed a significant decrease in SLAWD mRNA expression levels between the prepupal and adult stages. Interestingly, SLAWD expression was similarly down-regulated by treating 6th-stage larvae with DA. Growth- and development-related statistics confirmed the observed abnormalities in S. litura development after either RNAi or DA treatment.
  
  
  CONCLUSIONS
  SLAWD appears to have a biosynthetic function in the pupal and adult stages of S. litura. The toxic effect of DA on S. litura development is due the negative effect of DA on SLAWD gene expression.
authors.affiliation: Engineering Research Center of Biological Control, Ministry of Education, South China Agricultural University, Guangzhou, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Meng
authors.forename: Junjie
authors.initials: J
authors.lastname: Hu
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Xu
authors.forename: Zeqing
authors.initials: Z
authors.lastname: Wang
authors.forename: Qiongbu
authors.initials: Q
authors.lastname: Hu
authors.forename: Fengliang
authors.initials: F
authors.lastname: Jin
authors.forename: Shunxiang
authors.initials: S
authors.lastname: Ren
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018076:DNA, Complementary; D047630:Depsipeptides / Q000633:toxicity*; D018507:Gene Expression Regulation, Developmental; D019476:Insect Proteins / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009024:Morphogenesis; D016366:Open Reading Frames; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D034622:RNA Interference; D017386:Sequence Homology, Amino Acid; D018411:Spodoptera; D014921:Wings, Animal / Q000254:growth & development*
chemical_list: D018076:DNA, Complementary; D047630:Depsipeptides; D019476:Insect Proteins; C040423:destruxin A