POMP, pAb

The assembly of individual mammalian proteasome subunits into catalytically active 20S proteasome is a complex process, with biogenesis of the mammalian 20S proteasome occuring via precursor complexes containing α and unprocessed β subunits. The pro-peptides of the β subunits are thought to prevent premature conversion of the precursor complexes into matured particles and are needed for efficient β subunit incorporation. The complex biogenesis is tightly regulated, requiring additional components such as the maturation factor POMP (proteasome maturation protein), an ubiquitous protein in eukaryotic cells.