|Cooper, William - Rodney|
Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/15/2017
Publication Date: 6/29/2017
Citation: Garczynski, S.F., Martin, J.A., Griset, M.L., Willett, L.S., Cooper, W.R., Swisher, K.D., Unruh, T.R. 2017. CRISPR/Cas9 editing of the codling moth (Lepidoptera: Tortricidae) CpomOR1 gene affects egg production and viability. Journal of Economic Entomology. 110(4):1847-1855. Interpretive Summary: The codling moth is a worldwide insect pest of apple and pear, and new methods that are safe and effective are needed to control it. Scientists at the USDA-ARS Temperate Tree Fruit and Vegetable Research Unit in Wapato, WA used genomic technology to determine the function of a protein thought to be important in codling moth mating. This protein was inactivated using CRISPR/Cas9 genome editing. The results of this study revealed that inactivating this protein affected female codling moth's ability to lay viable eggs. In the future, strategies to inactivate this protein target in field populations could lead to new methods to control codling moth in the orchard.
Technical Abstract: The codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), is a major pest of pome fruit worldwide. The inclusion of semiochemicals, including the main sex pheromone (codlemone), in codling moth IPM programs has drastically reduced the amount of chemical insecticides needed to control this orchard pest. Odorant receptors located in sensory neuron membranes in the antennae are key sensors in the detection of semiochemicals and trigger downstream signaling events leading to a behavioral response. CpomOR1 is an odorant receptor belonging to the pheromone receptor subfamily in codling moth, and is a prime candidate for being a codlemone receptor based on its high expression levels in male antennae. In this study, the CpomOR1 gene was targeted using CRISPR/Cas9 genome editing to knock-down functional OR1 protein production to determine physiological function(s). By injecting early stage eggs, mutations were successfully introduced, including both deletions and insertions. When attempting to create stable populations of codling moth through mating of males with females containing mutations of the CpomOR1 gene, it was found that fecundity and fertility were affected, with edited females producing non-viable eggs. The role of CpomOR1 in fecundity and fertility in codling moth is unknown and will be the focus of future studies.