Ubiquitination: Protein Degradation

This lecture covers the process of ubiquitination, where ubiquitin is activated by an E1 enzyme, transferred to an E2 enzyme, and then to a substrate by an E3 enzyme. Different families of adaptor proteins recognize the substrate. Ubiquitination is reversible, with deubiquitinases removing ubiquitin. The lecture also discusses the role of ubiquitination in protein degradation, regulation of cell surface receptors, ion channels, stress response, ribosome biogenesis, viral infection, apoptosis, organelle biogenesis, cell cycle, transcription, immune response, and more. The lecture explains how the proteasome degrades proteins tagged with ubiquitin, and how proteins are selected for ubiquitination based on specific motifs or post-translational modifications.