簡要描述：Ubiquitin-dependent proteolysis mediates selective destruction of various cell cycle regulators, transcription factors and tumor suppressors. In eukaryotic cells, selective breakdown of cellular proteins is ensured by their ubiquitination and subsequent degradation by the 26S proteasome. At specific stages of development, embryo- and tissue-specific components of the 26S proteasome form, facilitating proteolysis. 20S Proteasome ?, also designated macropain subunit C2 or PROS-30, is a prosom