title: Analysis of persistent changes to γ-aminobutyric acid receptor gene expression in Plutella xylostella subjected to sublethal amounts of spinosad.
abstract: A multi-generational approach was used to investigate the persistent effects of a sub-lethal dose of spinosad in Plutella xylostella. The susceptibility of various sub-populations of P. xylostella to spinosad and the effects of the insecticide on the gene expression of γ-aminobutyric acid receptor (GABAR) were determined. The results of a leaf dip bioassay showed that the sensitivity of P. xylostella to spinosad decreased across generations. The sub-strains had been previously selected based on a determined LC25 of spinosad. Considering that GABA-gated chloride channels are the primary targets of spinosad, the cDNA of P. xylostella was used to clone GABARα by using reverse transcription-polymerase chain reaction (RT-PCR). The mature peptide cDNA was 1477-bp long and contained a 1449-bp open reading frame encoding a protein of 483 amino acids. The resulting amino acid sequence was used to generate a neighbor-joining dendrogram, and homology search was conducted using NCBI BLAST. The protein had high similarity with the known GABAR sequence from P. xylostella. Subsequent semi-quantitative RT-PCR and real-time PCR analyses indicated that the GABAR transcript levels in the spinosad-resistant strain (RR, 145.82-fold) and in Sub1 strain (selected with LC25 spinosad for one generation) were the highest, followed by those in the spinosad-susceptible strain, the Sub10 strain (selected for ten generations), and the Sub5 strain (selected for five generations). This multi-generational study found significant correlations between spinosad susceptibility and GABAR gene expression, providing insights into the long-term effects of sub-lethal insecticide exposure and its potential to lead to the development of insecticide-resistant insect populations.
authors.affiliation: Institute of Crop Protection, Guizhou University, Guiyang, China.
authors.forename: X-H
authors.initials: XH
authors.lastname: Yin
authors.affiliation: Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China.
authors.forename: Q-J
authors.initials: QJ
authors.lastname: Wu
authors.affiliation: Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China.
authors.forename: Y-J
authors.initials: YJ
authors.lastname: Zhang
authors.affiliation: Institute of Crop Protection, Guizhou University, Guiyang, China.
authors.forename: Y-H
authors.initials: YH
authors.lastname: Long
authors.affiliation: Institute of Crop Protection, Guizhou University, Guiyang, China.
authors.forename: X-M
authors.initials: XM
authors.lastname: Wu
authors.affiliation: Institute of Crop Protection, Guizhou University, Guiyang, China.
authors.forename: R-Y
authors.initials: RY
authors.lastname: Li
authors.affiliation: Institute of Crop Protection, Guizhou University, Guiyang, China.
authors.forename: M
authors.initials: M
authors.lastname: Wang
authors.affiliation: Institute of Crop Protection, Guizhou University, Guiyang, China.
authors.forename: X-L
authors.initials: XL
authors.lastname: Tian
authors.affiliation: College of Life Sciences, Hubei University, Wuhan, China.
authors.forename: X-G
authors.initials: XG
authors.lastname: Jiao
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D004338:Drug Combinations; D015870:Gene Expression; D019476:Insect Proteins / Q000096:biosynthesis / Q000235:genetics; D007305:Insecticide Resistance; D007306:Insecticides; D018942:Macrolides; D009036:Moths / Q000235:genetics* / Q000378:metabolism; D018079:Receptors, GABA / Q000096:biosynthesis / Q000235:genetics*
chemical_list: D004338:Drug Combinations; D019476:Insect Proteins; D007306:Insecticides; D018942:Macrolides; D018079:Receptors, GABA; C415329:spinosad