Molecular cloning and comparative analysis of transcripts encoding chemosensory proteins from two plant bugs, Lygus lineolaris and Lygus hesperus

Abstract

Chemosensory proteins (CSPs) are soluble carrier proteins typically characterized by a six-helix bundle structure joined by two disulfide bridges and a conserved Cys spacing pattern (C1-X 6-8 -C2-X 16-21 -C3-X 2 -C4). CSPs are functionally diverse with reported roles in chemosensation, immunity, development, and resistance. To expand our molecular understanding of CSP function in plant bugs, we used recently developed transcriptomic resources for Lygus lineolaris and Lygus hesperus to identify 17 and 14 CSP-like sequences, respectively. The Lygus CSPs are orthologous and share significant sequence identity with previously annotated CSPs. Three of the CSPs are predicted to deviate from the typical CSP structure with either five or seven helical segments rather than six. The seven helix CSP is further differentiated by an atypical C3-X 3 -C4 Cys spacing motif. Reverse transcriptase PCR-based profiling of CSP transcript abundance in adult L. lineolaris tissues revealed broad expression for most of the CSPs with antenna specific expression limited to a subset of the CSPs. Comparative sequence analyses and homology modeling suggest that variations in the amino acids that comprise the Lygus CSP binding pockets affect the size and nature of the ligands accommodated.

Biology, Ecology, and Pest Management of the Tarnished Plant Bug, Lygus lineolaris (Palisot de Beauvois) in Southern Row Crops

“…Hull et al [ 215 ] used homology-based cloning methods and transcriptome data mining to identify guanine-nucleotide binding proteins (G proteins) to elucidate the molecular mechanisms driving signal transduction in L. hesperus . Hull et al [ 216 ] recently defined the Lygus chemosensory proteins (CSPs) that play roles in chemosensation, development, immunity, and resistance. This study identified 17 CSP-like sequences in L. lineolaris and 14 sequences in L. hesperus , and these Lygus CSPs are orthologues and share sequence identity to previously annotated CSPs from other hemipterans.…”

A Chromosome scale assembly of the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), genome

“…Despite TPB being a pest of several economically important crops grown in North America, apart from a few population genetic and transcriptome and gene expression studies, there is a general paucity of research on the genetics of TPB [26][27][28][29][30][31]. Therefore, the development of a comprehensive set of genetic resources including a high-quality genome, full transcriptome with an o cial gene set that identi es all isoforms, and genetic markers suitable for population genomic and quantitative genetic studies is in need for this species.…”

A chromosome scale assembly of the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), genome

“…Despite TPB being a pest of several economically important crops grown in North America, apart from a few population genetic and transcriptome and gene expression studies, there is a general paucity of research on the genetics of TPB [ 26 – 31 ]. Therefore, the development of a comprehensive set of genetic resources including a high-quality genome, full transcriptome with an official gene set that identifies all isoforms, and genetic markers suitable for population genomic and quantitative genetic studies is needed for this species.…”