Research seminars Repair of damaged lysosomes

Abstract

Lysosomes are the main degradative organelles of the cell and also play key roles in metabolic signalling. On the other hand, because of their high content of protons, divalent cations and hydrolytic enzymes, lysosomes also can cause cell death if their integrity is compromised. Multiple agents, including pathogens, nanocrystals and amphiphilic drugs are indeed known to cause lysosome damage. Severely damaged lysosomes are therefore sequestered and degraded by an autophagic process known as lysophagy. Milder lysosome damage is reversible, and two molecular mechanisms have been identified to mediate lysosome repair. The first is comprised of the endosomal sorting complex required for transport (ESCRT) machinery, whereas the other involves contacts between the damaged lysosome and the endoplasmic reticulum (ER). These repair pathways will be the topic of this lecture.