The UPS operates through a series of highly regulated steps:
Ubiquitination: Proteins destined for degradation are tagged with a small protein called ubiquitin. This process involves three enzymes: E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3 (ubiquitin ligase). Proteasome Recognition: The ubiquitin-tagged proteins are recognized by the 26S proteasome, a large protease complex. Degradation: The proteasome degrades the tagged proteins into small peptides, which are then further broken down into amino acids by other cellular peptidases.
