Proteasome

Syllable breakdown

Dictionary meaning

A large, barrel-shaped protein complex found in all eukaryotic cells that degrades damaged, misfolded, or unneeded proteins by breaking them down into short peptide fragments. Proteins destined for proteasomal degradation are typically tagged with ubiquitin chains. The ubiquitin-proteasome system is essential for protein quality control and cell cycle regulation.

Examples

• The cancer drug bortezomib works by inhibiting the proteasome, causing toxic protein buildup in tumor cells.
• Scientists discovered that the proteasome plays a key role in regulating circadian rhythm proteins.