(190ay) CRISPR-Based Editing Reveals Edge-Specific Effects in Biological Networks

Unraveling the properties of biological networks is central to understanding normal and disease cellular phenotypes. Networks consist of functional elements (nodes) that form a variety of diverse connections (edges) with each node being a hub for multiple edges. Herein, in contrast to node-centric network perturbation and analysis approaches, we present a CRISPR-based methodology for delineating the role of network edges. High throughput ablation of network edges using a library targeting 93 miRNA target sites in 71 genes reveals numerus edges that control cellular survival under stress. To specifically compare the impact of removing nodes versus edges in a biological network, we dissect a p53-microRNA pathway. We show that removal of the miR-34a target site from the anti-apoptotic gene Bcl-2 desensitizes the cell from ectopic expression of miR-34a mimics in a p53-depedent manner. In summary, we demonstrate that network edges are critical to the function and stability of biological networks. Our results introduce a novel genetic screening opportunity via edge ablation and highlight a new dimension in biological network analysis.