The cys‐loop ligand‐gated ion channel gene superfamilies of the cockroaches Blattella germanica and Periplaneta americana

Abstract

BACKGROUND Cockroaches are serious urban pests that can transfer disease‐causing microorganisms as well as trigger allergic reactions and asthma. They are commonly managed by pesticides that act on cys‐loop ligand‐gated ion channels (cysLGIC). To provide further information that will enhance our understanding of how insecticides act on their molecular targets in cockroaches, we used genome and reverse transcriptase polymerase chain reaction (RT‐PCR) data to characterize the cysLGIC gene superfamilies from Blattella germanica and Periplaneta americana. RESULTS The B. germanica and P. americana cysLGIC superfamilies consist of 30 and 32 subunit‐encoding genes, respectively, which are the largest insect cysLGIC superfamilies characterized to date. As with other insects, the cockroaches possess ion channels predicted to be gated by acetylcholine, γ‐aminobutyric acid, glutamate and histamine, as well as orthologues of the drosophila pH‐sensitive chloride channel (pHCl), CG8916 and CG12344. The large cysLGIC superfamilies of cockroaches are a result of an expanded number of divergent nicotinic acetylcholine receptor subunits, with B. germanica and P. americana, respectively, possessing eight and ten subunit genes. Diversity of the cockroach cysLGICs is also broadened by alternative splicing and RNA A‐to‐I editing. Unusually, both cockroach species possess a second glutamate‐gated chloride channel as well as another CG8916 subunit. CONCLUSION These findings on B. germanica and P. americana enhance our understanding of the evolution of the insect cysLGIC superfamily and provide a useful basis for the study of their function, the detection and management of insecticide resistance, and for the development of improved pesticides with greater specificity towards these major pests. © 2020 Society of Chemical Industry

Contact Toxicity of Various Stemona Collinsiae Root Extracts Against Periplaneta Americana (Dictyoptera: Blattodea) And Detection of Didehydrostemofoline Distribution in Tissue Using MALDI Imaging Mass Spectrometry

“…These scientific reports showed that S. collinsiae possessed contact toxicity that could eliminate pest and insect vectors. P. americana, an important medical insect vector that is resistant to insecticides and hard to kill [39][40][41][42][43] has never been tested with S. collinsiae root extracts. Nymphicidal and adulticidal activities of S. collinsiae against P. americana via topical administration are unknown.…”

The Hair Cell α9α10 Nicotinic Acetylcholine Receptor: Odd Cousin in an Old Family

“…Numerous phylogenetic analyses of the subfamily of nAChR subunits have been performed (Ortells and Lunt, 1995 ; Le Novere and Changeux, 1995 ; Tsunoyama and Gojobori, 1998 ; Dent, 2006 ; Franchini and Elgoyhen, 2006 ; Lipovsek et al, 2012 ; Li et al, 2016 ; Faltine-Gonzalez and Layden, 2019 ; Jiao et al, 2019 ; Pedersen et al, 2019 ; Marcovich et al, 2020 ; Jones et al, 2021 ). Some of them date to the pre-genomic era, including a small number of coding sequences and leading to less informative iterations of phylogenetic tree topologies.…”

Understanding the biological action of insecticides is the key to their continuous improvement

“…Jones et al . contributed a detailed sequence analysis of the cys‐loop superfamily of ligand‐gated ion channels in cockroaches 20 . This superfamily includes many well‐known insecticide targets, including the nicotinic receptors and GABA gated ion channels discussed elsewhere in this special issue.…”