title: Identification of a thioredoxin peroxidase gene involved in resistance to nucleopolyhedrovirus infection in Helicoverpa armigera with RNA interference.
abstract: Thioredoxin peroxidases (Tpxs) play a crucial role in protection against oxidative damage in several insect species. However, studies on the characteristics and functions of Tpxs in Helicoverpa armigera are lacking. In this study, a novel 2-Cys Tpx gene from H. armigera (HaTpx) was identified. Sequence analysis revealed that HaTpx is highly conserved and shares two catalysis regions (VCP) with other insect species. HaTpx mRNA was found to be expressed in an age-dependent manner and was ubiquitous in all tissues examined. Hormone treatment showed that the expression of HaTpx is clearly induced by 20-hydroxyecdysone but repressed by Juvenile hormone. Additionally, extreme temperature, ultraviolet light, mechanical injury, Escherichia coli, Metarhizium anisopliae, nucleopolyhedrovirus (NPV) infection, and H2O2 treatment markedly induced HaTpx gene expression. Reactive oxygen species (ROS) levels in hemocytes and MDA concentrations in the hemolymph after NPV infection were evaluated, and the results indicated that NPV infection causes excessive ROS generation. After knockdown of HaTpx by RNA interference, the expression of three antioxidant genes (Cu/ZnSOD, Trx, and TrxR) was increased, whereas two antioxidant genes (CAT and GPX) showed decreased expression. Moreover, the susceptibility of H. armigera to NPV infection increased after HaTpx knockdown. These results indicated that HaTpx contributes to the susceptibility of H. armigera to NPV, and the results also provide a theoretical basis for a novel strategy for developing new chemicals and microbial pesticides that target HaTpx gene for controlling H. armigera.
authors.affiliation: Department of Entomology, China Agricultural University, Beijing 100193, China.
authors.forename: Songdou
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Department of Entomology, China Agricultural University, Beijing 100193, China.
authors.forename: Zhongjian
authors.initials: Z
authors.lastname: Shen
authors.affiliation: Department of Entomology, China Agricultural University, Beijing 100193, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Entomology, China Agricultural University, Beijing 100193, China.
authors.forename: Fengming
authors.initials: F
authors.lastname: Wu
authors.affiliation: Department of Entomology, China Agricultural University, Beijing 100193, China.
authors.forename: Boyu
authors.initials: B
authors.lastname: Zhang
authors.affiliation: Department of Entomology, China Agricultural University, Beijing 100193, China.
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Entomology, China Agricultural University, Beijing 100193, China.
authors.forename: Qingwen
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Entomology, China Agricultural University, Beijing 100193, China. Electronic address: liuxiaoxia611@cau.edu.cn.
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Liu
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D004441:Ecdysterone / Q000494:pharmacology; D018507:Gene Expression Regulation, Developmental; D006434:Hemocytes / Q000737:chemistry; D006458:Hemolymph / Q000737:chemistry; D007605:Juvenile Hormones / Q000494:pharmacology; D007814:Larva / Q000201:enzymology / Q000235:genetics / Q000821:virology; D009036:Moths / Q000201:enzymology / Q000235:genetics* / Q000821:virology*; D017924:Nucleopolyhedroviruses / Q000502:physiology*; D054464:Peroxiredoxins / Q000235:genetics*; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000032:analysis; D017423:Sequence Analysis, RNA; D013312:Stress, Physiological
chemical_list: D000975:Antioxidants; D007605:Juvenile Hormones; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D004441:Ecdysterone; D054464:Peroxiredoxins
keywords: Helicoverpa armigera; Hormone; Nucleopolyhedrovirus; RNA interference; Thioredoxin peroxidase; Various stress