Molecular Cloning and Expression Profiling of Minus-C Odorant Binding Proteins from Apocheima cinerarius (Lepidoptera: Geometridae)1

Abstract

Based on transcriptome data of adults and pupae, 3 Minus-C OBPs (odorant binding proteins) genes were cloned and analyzed in various tissues (including head, thorax, abdomen, legs of female and male adults, and wings of males) of Apocheima cinerarius Erschoff (Lepidoptera: Geometridae). Expression patterns were examined across the developmental stages of egg, larva (1st–5th instars), pupa (non-diapause and diapause), and adults. The qRT-PCR results revealed a significant up-regulation of OBP8 in 3rd and 4th larval instars, with the highest expression level observed in 4th-instar larvae. OBP14 exhibited higher expression levels in diapausing pupal and adult stages, with highest levels in the female adult. Conversely, OBP18 displayed highest expression in the non-diapausing pupae, while exhibiting extremely low expression levels among other stages. The tissue expression profile revealed a gradual increase in the expression of OBP14, with highest levels in the male legs, whereas the expression pattern of OBP18 exhibited an inverse trend with maximum expression observed in the male head (including antennae). OBP8 exhibited high expression levels in the abdomen of the female adult, while OBP14 showed high expression in the legs of the male adult. Additionally, OBP18 displayed high expression in the female head. These findings suggest the crucial role played by OBP genes in both olfactory and non-olfactory tissues of A. cinerarius. The results provide a fundamental basis for further investigation into the recognition of odorant binding in A. cinerarius.