The UDP-Glycosyltransferase Gene Family in Achelura yunnanensis (Lepidoptera: Zygaenidae): Identification, Phylogeny, and Diverse Expression Patterns

The caterpillars of the Lepidoptera are important herbivores as most of them belong to serious agricultural and forestry pests. To adapt to their habitats and feeding host plants, the larvae utilize uridine diphosphate (UDP)-glycosyltransferases (UGTs) to metabolize plant defensive compounds and insecticides. However, information on the UGT gene family in Achelura yunnanensis remains scarce. Here, we characterized the UGT genes through gene identification, phylogenic analyses, and comprehensive expression profiles regarding sexes, tissues, and stages. Transcriptome analyses led to the yields of 50 transcripts encoding UGTs in A. yunnanensis, representing a comparable gene number compared to those in other lepidopteran species. Sequence and phylogenetic analyses revealed a low amino acid identity of 28.23% among 31 full-length AyunUGTs, but some members shared relatively high conservation (>50% identities) with a phylogenetically clustered distribution. In addition, the majority of AyunUGTs possessed conserved residues involved in the catalysis and sugar-donor binding. Combining RNA sequencing and PCR approaches, a number of AyunUGTs were found to have the expression in chemosensory or detoxification tissues, possibly associated with the sensing of odorant molecules and the metabolism of toxic chemicals. More importantly, at least 27 AyunUGTs displayed detectable expression in reproductive tissues of both sexes. This study identifies candidate A. yunnanensis UGTs responsible for detoxification, olfaction, and reproduction, allowing us to address putative roles of UGTs in the adaptation of larvae to the habitats and feeding hosts.