Location: Horticultural Crops Research UnitTitle: Identification and characterization of pyrokinin and CAPA peptides, and corresponding GPCRs from spotted wing drosophila, Drosophila suzukii
|JOON-AHN, SEUNG - Oregon State University|
|KIM, A-YOUNG - Hallym University|
|KOH, YOUNG HO - Hallym University|
Submitted to: General and Comparative Endocrinology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/5/2017
Publication Date: 1/7/2017
Citation: Choi, M.Y., Joon-Ahn, S., Kim, A., Koh, Y. 2017. Identification and characterization of pyrokinin and CAPA peptides, and corresponding GPCRs from spotted wing drosophila, Drosophila suzukii. General and Comparative Endocrinology. 246:354-362. doi: 10.1016/j.ygcen.2017.01.011.
Interpretive Summary: Spotted wing drosophila (SWD), Drosophila suzukii, is a destructive invasive pest introduced from Asia, and attacks a wide range of ripening fruits including all cherry crops. Since the first outbreak in California 2008 the distribution of SWD is rapidly expanding across the U.S., Canada and Europe. The estimated economic impact from crop yield loss, drop in market value, and higher management cost is hundreds of millions of dollars in the U.S. alone, and increasing every year. Recently, SWD management has been ranked a top research priority by small fruit growers. To replace or reduce the use of chemical insecticides, currently alternative options are being developed, but there are still many critical gaps to be implemented against SWD in field. Neuropeptides are the largest group of insect hormones known to regulate a variety of physiological functions. The FXPRLamide family peptides are based on the core active amino acids at the C-terminal ends with diverse functions across the Insecta. They serve many functions with many different names: pyrokinin (PK), pheromone biosynthesis activating neuropeptides (PBAN), diapause hormone (DH), and CAPA (capability)-pyrokinin (CAPA-PK). Receptors of insect neuropeptides are belonged to the family of G protein-coupled receptors (GPCRs), and particularly important because these receptors are involved in almost all biological functions in insect life stages. Therefore, these receptors might be good targets to develop insect control method. Scientists from USDA-ARS at Corvallis, OR, Oregon State University and Hallym University identified and characterized two neuropeptide genes and their receptors, possibly offer a novel control method for this pest insect in the future.
Technical Abstract: To date, some biological activities have been confirmed as different named peptides, however, most FXPRLamide peptides are still poorly understood although these peptides are found in all insects. So, the study of receptors for these peptides is particularly important. Receptors of FXPRLamide peptides belong to the family of G-protein-coupled receptors (GPCRs). These receptors are closely related and are categorized into two types of GPCRs: PK receptor (PKr) activated by 1) pyrokinin/PBAN, and DH-like receptor (DHr) activated by diapause hormone (DH)/DH-like. In this study we identified and characterized PK and CAPA genes encoding two FXPRLamide peptides, pyrokinin and CAPA-DH, and two corresponding GPCRs from spotted wing drosophila (SWD), Drosophila suzukii. Expressions of PK and CAPA mRNAs were differentially observed during all life stages except the embryo, and the detection of CAPA transcription was relatively strong compared with the PK gene in SWD. Both D. suzukii pyrokinin receptor and CAPA-DH receptor were functionally expressed and confirmed through binding to PK and DH peptides. Differential expression of two GPCRs occurred during all life stages; a strong transcription of DrosuPKr was observed in the 3rd instar. DrosuCAPA-DHr was clearly expressed from the embryo to the larval stage, but not detected in the adult. Gene regulation during the life stages was not synchronized between ligand and receptor. As compared genes of SWD PK, CAPA, PKr and CAPA-DHr to four corresponding genes of D. melanogaster, SWD CAPA and the receptor genes are more similar to D. melanogaster than PK and the receptor genes. These data suggest that the CAPA gene could be evolutionally more conserved to have a common biological role in insects. Our results provide potential biological function(s) of PK and CAPA-DH peptides in SWD, and possibly offer a novel control method for this pest insect in the future.