Identification and sex-biased expression analysis of olfactory-related genes in Lymantria dispar based on transcriptome and qRT-PCR

Abstract

Lymantria dispar, a destructive forest pest, poses a significant threat to forest ecosystems. Olfaction plays a pivotal role in mate finding, host location, and oviposition site selection in insects. This study aimed to systematically characterize olfactory-related genes in adult L. dispar and examine sex-specific expression profiles, shedding light on the molecular mechanisms of olfactory perception in this species. Antennal transcriptomes of male and female L. dispar were sequenced, generating 36.61 Gb of high-quality clean data. A total of 134 olfactory-related genes were identified, including 40 odorant receptors (ORs), 12 gustatory receptors (GRs), 20 ionotropic receptors (IRs), 17 chemosensory proteins (CSPs), 38 odorant-binding proteins (OBPs), 3 odorant-degrading enzymes (ODEs), and 4 sensory neuron membrane proteins (SNMPs). Relative expression levels of these genes were validated by qRT-PCR, revealing that 28 genes were significantly upregulated in female antennae, while 32 genes exhibited higher expression in males. These findings aligned closely with the transcriptome data. This study provides a comprehensive characterization of olfactory-related genes in L. dispar antennae and uncovers their sex-biased expression, offering valuable insights into the molecular mechanisms of pheromone detection and other olfactory-driven behaviors in this pest species.