title: Identification and expression of caspase-1 gene under heat stress in insecticide-susceptible and -resistant Plutella xylostella (Lepidoptera: Plutellidae).
abstract: A caspase gene in Plutella xylostella (DBM) was identified firstly and named Px-caspase-1. It had a full-length of 1172 bp and contained 900 bp open reading frame that encoded 300 amino acids with 33.6 kDa. The deduced amino acid of Px-caspase-1 had two domain profile including caspase_p20 (position 61-184) and caspase_p10 (position 203-298) (i.e. the big and small catalytic domains), and the highly conserved pentapeptide QACQG in caspase_p20 domain (the recognized catalytic site of caspases). Being highly homologous to effector caspase genes in other insect and mammalian species, Px-caspase-1 was thought to be an effector caspase gene. Heat stress could result in significant mortality increase on adult DBM. Px-caspase-1 mRNA expression and caspase-3 enzyme activity (a effector caspase) were elevated with age and heat treatment. And, heat stress facilitated the procession of Px-caspase-1 expression. Significantly higher mRNA transcription levels were found in a chlorpyrifos-resistant DBM strain, as compared to those in insecticide-susceptible DBM. The results indicated that high temperature could significantly promote apoptosis process resulting in an the increased DBM mortality rate, and that insecticide-susceptible DBM had a significantly higher physiological fitness at high temperatures than insecticide-resistant DBM.
authors.affiliation: Department of Plant Protection, Key Laboratory of Biopesticide and Chemical Biology, Fujian Agriculture and Forestry University, Ministry of Education, Fuzhou, 350002, Fujian Province, China.
authors.forename: Hua Mei
authors.initials: HM
authors.lastname: Zhuang
authors.forename: Kuan Fu
authors.initials: KF
authors.lastname: Wang
authors.forename: Tadashi
authors.initials: T
authors.lastname: Miyata
authors.forename: Zu Jian
authors.initials: ZJ
authors.lastname: Wu
authors.forename: Gang
authors.initials: G
authors.lastname: Wu
authors.forename: Lian Hui
authors.initials: LH
authors.lastname: Xie
mesh_terms: D000367:Age Factors; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D020170:Caspase 1 / Q000235:genetics* / Q000378:metabolism*; D004390:Chlorpyrifos; D017931:DNA Primers / Q000235:genetics; D018869:Heat-Shock Response / Q000235:genetics*; D007305:Insecticide Resistance / Q000235:genetics / Q000502:physiology*; D008969:Molecular Sequence Data; D009036:Moths / Q000378:metabolism*; D011487:Protein Conformation; D017422:Sequence Analysis, DNA
chemical_list: D017931:DNA Primers; D020170:Caspase 1; D004390:Chlorpyrifos