Antennal Transcriptome Analysis and Identification of Candidate Chemosensory Genes of the Harlequin Ladybird Beetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae)

Abstract

In predatory ladybirds (Coleoptera: Coccinellidae), antennae are important for chemosensory reception used during food and mate location, and for finding a suitable oviposition habitat. Based on NextSeq 550 Illumina sequencing, we assembled the antennal transcriptome of mated Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) males and females and described the first chemosensory gene repertoire expressed in this species. We annotated candidate chemosensory sequences encoding 26 odorant receptors (including the coreceptor, Orco), 17 gustatory receptors, 27 ionotropic receptors, 31 odorant-binding proteins, 12 chemosensory proteins, and 4 sensory neuron membrane proteins. Maximum-likelihood phylogenetic analyses allowed to assign candidate H. axyridis chemosensory genes to previously described groups in each of these families. Differential expression analysis between males and females revealed low variability between sexes, possibly reflecting the known absence of relevant sexual dimorphism in the structure of the antennae and in the distribution and abundance of the sensilla. However, we revealed significant differences in expression of three chemosensory genes, namely two male-biased odorant-binding proteins and one male-biased odorant receptor, suggesting their possible involvement in pheromone detection. Our data pave the way for improving the understanding of the molecular basis of chemosensory reception in Coccinellidae.

Antennal transcriptome analysis of chemosensory genes in the cowpea beetle, Callosobruchus maculatus (F.)

“…Alternatively, antennal transcriptomic analyses have been performed (e.g. [ 27 – 29 ]). For example, chemosensory gene families have been identified in various chrysomelid beetles, including Colaphellus bowringi Baly [ 30 ], L .…”

“…Alternatively, antennal transcriptomic analyses have been performed (e.g. [27][28][29]). For example, chemosensory gene families have been identified in various chrysomelid beetles, including Colaphellus bowringi Baly [30], L. decemlineata [31], Ambrostoma quadriimpressum Motschulsky [32], Phyllotreta striolata (F.) [33], Pyrrhalta maculicollis (Mots.…”

Expression Profiling and Functional Analysis of Candidate Odorant Receptors in Galeruca daurica

“…We speculate that our use of a high-throughput sequencing approach using whole insects rather than antennae may result in a significant number of olfactory genes being buried. Expression profiling of chemosensory genes are of primary importance for exploring the function and the olfactory recognition mechanism of insects [ 31 , 32 , 33 ]. The tissue expression profiles of 21 ORs showed that most OR genes ( GdauOR1 , GdauOR3 - 6 , GdauOR8 , GdauOR11 - 13 , GdauOR15 , GdauOR17 - 20 , and GdauORco ) were highly expressed in antennae, which were similar to the results in other species [ 9 ].…”

Effect of victim relatedness on cannibalistic behaviour of ladybird beetle,Menochilus sexmaculatusFabricius (Coleoptera: Coccinellidae)

“…In addition, earlier studies have reported that the larval instars and adults can assess the surface chemical profile (Agarwala et al , 1998; Omkar et al ., 2004). In Hippodamia variegata Goeze (Xie et al ., 2022) and H. axyridis (Rondoni et al ., 2021), antennal transcriptomes have reported the presence of odorant receptors and their chemosensory role in prey recognition and searching behaviour. Studies involving the role of family-specific chemical profiles in kin recognition have also been reported (Wong et al , 2014; Weiss and Schneider, 2021).…”