Using the CRISPR/Cas9 System for Dissection of Functional Sites of the Notch Gene in Drosophila melanogaster.

The Notch gene is a key factor in the signaling cascade that allows communication between neighboring cells in many organisms, from worms and insects to humans. The relative simplicity of the Notch pathway in Drosophila, combined with a powerful set of molecular and cytogenetic methods, makes this model attractive for studying the fundamental principles of Notch regulation and functioning. Here, using the CRISPR/Cas9 system in combination with homologous recombination, for the first time at the level of the whole organism, we obtained a directed deletion of the 5'-regulatory region and the first exon of the Notch gene, which were replaced by the attP integration site of the ΦC31 phage. Based on this approach, we obtained and characterized new Notch mutations. Thus, a new powerful tool is provided for studying the genetic regulation of the Notch gene and the organization of chromatin at this locus.