Environmental stresses induce the expression of putative glycine‐rich insect cuticular protein genes in adult Leptinotarsa decemlineata (Say)

Abstract

The deposition of cuticular proteins in insects usually occurs during the moulting process. Three putative glycine-rich insect cuticular proteins, Ld-GRP1 to 3, were identified and characterized from the Colorado potato beetle, Leptinotarsa decemlineata. The Ld-GRPs contained conserved GXGX and/or GGXG sequence repeats. Ld-GRP1 also contained a conserved AAPA/V motif commonly found in cuticular proteins. The transcripts of Ld-GRP1 and Ld-GRP2 were detected in the epidermal cell layer by in situ hybridization, making them putative insect cuticular proteins. The putative cuticular protein genes were highly induced by the insecticide azinphosmethyl (organophosphorous) 2-3 weeks after adult moulting. Putative cuticular protein gene expression level was higher in azinphosmethyl-resistant beetles than in susceptible beetles. Furthermore, two of the putative cuticular protein genes were highly induced by dry environmental conditions. These results suggest that the insect might increase cuticular component deposition in the adult stage in response to environmental stresses. This ability may allow the insect to adapt to new or changing environments.

Down-regulation of gene expression between the diapause initiation and maintenance phases of the Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)

“…The cuticle is a dynamic structure that responds to external factors such as insecticides and desiccation (Zhang et al, 2008). In response to photoperiodism, the expression of four glycine-rich cuticle protein genes from the Colorado potato beetle have been shown to persist four days longer in diapause IP adult beetles than in early nondiapausing adults (Yocum et al, 2009).…”

Population Dynamics and Transcriptomic Responses of Chorthippus albonemus (Orthoptera: Acrididae) to Herbivore Grazing Intensity

“…Polyproteins have been reported to play a role in virus resistance in plants (Ponz et al, 1988;Reddy et al, 2001), but have not been wellstudied in grasshoppers. Cuticular protein genes, which were upregulated in the high grazing and overgrazing plots, may play an important role in stress resistance, as demonstrated by changes in body cuticle that occur in response to environmental stress and poor food quality (Zhang et al, 2008). Furthermore, the upregulated genes were primarily involved in serine-type peptidase activity and chitin metabolic processes, whereas the downregulated genes were primarily involved in the structural constituents of cuticle, structural molecule activity, and the ribosome.…”

Integrated Metabonomic−Proteomic Analysis of an Insect−Bacterial Symbiotic System

“…Differences in expression of genes for cuticular proteins have also been obtained across aphids with different reproductive modes 42 and in the beetle Leptinotarsa decemlineata in response to an organophosphorous insecticide and to water stress. 43 Three additional proteins with function not directly related to metabolism are also of particular note. First, the translationally controlled tumor protein is an abundantly expressed protein in many animals, including insects, 44 and plays a role in the regulation of insect growth.…”