Project: Mi(gh)ty CRISPR: developing CRISPR/Cas9 as a functional genetic tool for spider mite research

2020-01-01 – 2023-12-31

Abstract

The spider mite Tetranychus urticae belongs to the Chelicerata, the second largest group of terrestrial animals, and is an important crop pest worldwide It is an extreme generalist herbivore that rapidly develops resistance to pesticides The molecular mechanisms underlying spider mite adaptation to xenobiotic compounds (pesticides and plant defense molecules) has been untangled to some extent However, reliable tools for genome editing that can provide proof of principle for the involvement of genes and mutations in spider mite adaptation are currently non-existent CRISPR/Cas9 has revolutionized functional genetic work in many organisms but, although straightforward for many model and non-model arthropods, has never been successful in chelicerates up to this day Injection of the Cas9/sgRNA complex into the embryo is crucial for CRISPR/Cas9 in arthropods, but currently this is not feasible for chelicerates as eggs die after injection Very recently, it was shown that a yolk protein could be used for Cas9 protein delivery into oocytes after injection of female mosquitoes, circumventing traditional embryo injections This greatly improves Cas9 uptake by the oocytes, a groundbreaking discovery, but not readily applicable for mites In this project, we want to design a Cas9 delivery system tailored to spider mites, providing a unique tool for genome editing in this species and potentially paving the way for transformation in the large group of Chelicerates