Genome-wide analysis of G protein-coupled receptors required for development and reproduction in Tribolium castaneum

The G protein-coupled receptors (GPCRs) belong to a large superfamily of integral cell membrane proteins and play crucial roles in physiological processes such as behavior, development and reproduction. To understand the role of GPCRs in regulation of development and reproduction, we used bioinformatics approaches and identified a total of 118 non-sensory GPCRs that belong to A, B, C and D classes from the Tribolium castaneum genome. Microarray analyses using chips containing 60-mer oligonucleotides representing 15,208 predicted genes of T. castaneum showed stage- and tissue-specific expression for most GPCRs analyzed. More than 100 GPCRs were assessed for their effects on development and reproduction using RNA interference (RNAi). We identified 25 GPCRs that are required for egg production, 27 GPCRs required for embryogenesis and one GPCR in the Cadherin family required for pupal-adult metamorphosis. This study, the first systematic and functional genomic screening for non-sensory GPCRs from T. castaneum, showed that T. castaneum is an excellent model insect for uncovering the physiological roles of insect GPCRs. Combining functional genomics and physiological analysis we will be able to characterize additional GPCRs leading to the development of novel pesticides targeting these receptors. Supported by NIH grant, GM070559-04