Analysis of the whole developmental period reveals stage-specific gene expression profiles of the Indianmeal moth, Plodia interpunctella

The Indianmeal moth, Plodia interpunctella, is a global pest of stored and processed food products. Although its biology and management have been widely studied, there is limited information on the roles of specific genes during development at the molecular level. To get better understanding of physiological roles of each gene underlying in insect development, it is necessary to determine the precise and comprehensive profiles of each gene throughout development. Here, we determined the whole developmental expression patterns of 13 genes related to growth, stress, metabolism, and host defense by using quantitative real-time RT-PCR. Our results showed that the expression profiles of the 13 genes were unique throughout the development of P. interpunctella. Expression levels of stress-associated genes such as heat-shock protein genes (hsps) and an antioxidant gene, thioredoxin peroxidase (Tpx), were highest in both egg and adult stages. Expression levels of both ecdysone receptor (EcR) and ultraspiracle (USP) were differentially the highest in the pupal and wandering phase of the fifth instar larvae, respectively. Expression levels of immune-related genes such as hemolin and β-1,3 glucan recognition protein (βgrp) were the highest during the wandering larval and pupal stages, while those of prophenoloxidase (ProPO), superoxide dismutase (SOD), and two storage protein genes (SP1 and SP2) were the highest during the wandering larval stage. This study provides comprehensive insights for understanding the functional roles of genes especially hsps and Tpx, which are stage-specifically regulated during the development of P. interpunctella.