Determining the Molecular Mechanisms Regulating Lysosome Damage & Repair Pathways (360G-Wellcome-202061_Z_16_Z)

Lysosomes are ubiquitous membrane bound organelles that when ruptured, release hydrolytic enzymes and Hydrogen ions into the cytoplasm. This can result in DNA damage, impeded degradation of lysosomal substrates, inflammation and neurodegenerative diseases. Understanding how cells respond to such stress and how the repair/removal pathways are regulated is paramount to controlling cellular and tissue homeostasis as well as developing future therapeutic strategies. Currently, a number of stimuli can induce lysosomal damage and rupture, including bacterial pathogens, viruses, Silica crystals and lysosomotrophic agents (LLOMe). In addition, inducing lysosome damage in cancer cells with high levels of cathepsins is seen as a viable therapeutic option. However, there is a serious lack of knowledge regarding the lysosome damage sensing, repair or removal mechanisms that are initiated upon lysosomal permeablization. Therefore, I propose to use a siRNA screen to identify key regulators of this process, with particular emphasis on potentially druggable targets. We will focus our efforts on Kinases, phosphatases, de-ubiquitinases and membrane trafficking genes. By the end of this study, I hope to identify a number of candidate genes to take forward for more in-depth analysis with particular focus on regulation of bacterial infection and lysosome induced cancer cell death pathways.