scholarly journals Molecular characterization of sugar taste receptors in the cotton bollworm Helicoverpa armigera

Genome ◽  
2017 ◽  
Vol 60 (12) ◽  
pp. 1037-1044 ◽  
Author(s):  
Wei Xu ◽  
Naiyong Liu ◽  
Yalin Liao ◽  
Alisha Anderson
Keyword(s):  
Helicoverpa Armigera ◽  
Stop Codon ◽  
Critical Role ◽  
Cotton Bollworm ◽  
Pcr Analysis ◽  
Male Adult ◽  
Reading Frame ◽  
Frame Sequence ◽  
Helicoverpa Armígera ◽  
Sugar Receptors

Insects utilize sugars as their essential energy and nutrient sources; therefore, the sense of sugar detection plays a critical role in insect behaviours. Previously, using genomic and transcriptomic approaches, we identified eight putative sugar gustatory receptor (GR) genes from the cotton bollworm Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae). Here, we further validated these annotated sugar receptor genes (HarmGr4–HarmGr8 and HarmGr10–HarmGr12) and found HarmGr10 may be a pseudogene carrying a stop codon in the open reading frame. Sequence alignment revealed H. armigera sugar GR sequences are conserved at C-terminus and phylogenetic analysis showed that insect sugar GRs have evolved in a family-specific manner. Interestingly, all eight H. armigera sugar GRs are localized in a tandem array on the same scaffold of the genome. In silico gene expression and reverse transcription (RT)-PCR analysis showed that HarmGr10 is specifically expressed in male adult testes while HarmGr11 is specifically expressed in female adult ovaries, suggesting H. armigera sugar GRs may be involved in reproduction-related functions. This study improves our knowledge on insect sugar receptors and gustatory systems.

scholarly journals Molecular identification, characterization, and expression analysis of a serine protease inhibitor gene from cotton bollworm, Helicoverpa armigera (Lepidoptera: Noctuidae)

2020 ◽  
Author(s):  
Muhammad Shakeel
Keyword(s):  
Protease Inhibitor ◽  
Serine Protease ◽  
Protease Inhibitors ◽  
Helicoverpa Armigera ◽  
Fat Body ◽  
Critical Role ◽  
Functional Characterization ◽  
Serine Protease Inhibitor ◽  
Cotton Bollworm ◽  
Helicoverpa Armígera

Abstract Serine protease inhibitors (serpins), a superfamily of protease inhibitors, are known to be involved in several physiological processes, such as development, metamorphosis, and innate immunity. In our study, a full-length serpin cDNA, designated Haserpin1, was isolated from the cotton bollworm Helicoverpa armigera. The cDNA sequence of Haserpin1 is 1176 nt long, with an open reading frame encoding 391 amino acids; there is one exon and no intron. The predicted molecular weight of Haserpin1 is 43.53 kDa, with an isoelectric point of 4.98. InterProScan was employed for Haserpin1 functional characterization, which revealed that Haserpin1 contains highly conserved signature motifs, including a reactive center loop (RCL) with a hinge region (E341–N350), the serpin signature, (F367–F375) and a predicted P1–P1′ cleavage site (L357–S358), which are useful for identifying serpins. Transcripts of Haserpin1 were constitutively expressed in the fat body, suggesting that it is the major site for serpin synthesis. During the developmental stages, a fluctuation in the expression level of Haserpin1 was observed, with low expression detected at the 5th-instar larval stage. In contrast, relatively high expression was detected at the prepupal stage, suggesting that Haserpin1 might play a critical role at the H. armigera wandering stage. Although the detailed function of this serpin (Haserpin1) needs to be elucidated, our study provides a perspective for the functional investigation of serine protease inhibitor genes.

Broad-scale suppression of cotton bollworm, Helicoverpa armigera (Lepidoptera: Noctuidae), associated with Bt cotton crops in Northern New South Wales, Australia

2016 ◽  
Vol 107 (2) ◽  
pp. 188-199 ◽  
Author(s):  
G.H. Baker ◽  
C.R. Tann
Keyword(s):  
Host Plant ◽  
Helicoverpa Armigera ◽  
Cotton Bollworm ◽  
Bt Cotton ◽  
Cotton Production ◽  
Bt Toxin ◽  
Pheromone Trapping ◽  
Eastern Australia ◽  
Helicoverpa Armígera ◽  
Broad Scale

AbstractThe cotton bollworm, Helicoverpa armigera, is a major pest of many agricultural crops in several countries, including Australia. Transgenic cotton, expressing a single Bt toxin, was first used in the 1990s to control H. armigera and other lepidopteran pests. Landscape scale or greater pest suppression has been reported in some countries using this technology. However, a long-term, broad-scale pheromone trapping program for H. armigera in a mixed cropping region in eastern Australia caught more moths during the deployment of single Bt toxin cotton (Ingard®) (1996–2004) than in previous years. This response can be attributed, at least in part, to (1) a precautionary cap (30% of total cotton grown, by area) being applied to Ingard® to restrict the development of Bt resistance in the pest, and (2) during the Ingard® era, cotton production greatly increased (as did that of another host plant, sorghum) and H. armigera (in particular the 3rd and older generations) responded in concert with this increase in host plant availability. However, with the replacement of Ingard® with Bollgard II® cotton (containing two different Bt toxins) in 2005, and recovery of the cotton industry from prevailing drought, H. armigera failed to track increased host-plant supply and moth numbers decreased. Greater toxicity of the two gene product, introduction of no cap on Bt cotton proportion, and an increase in natural enemy abundance are suggested as the most likely mechanisms responsible for the suppression observed.

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