Identification of proteassemblin, a mammalian homologue of the yeast protein, Ump1p, that is required for normal proteasome assembly
Related Experiment Video
Updated: Aug 2, 2026

Assaying Proteasomal Degradation in a Cell-free System in Plants
Published on: March 26, 2014
T A Griffin1, J P Slack, T S McCluskey
1William S. Rowe Division of Rheumatology, Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, Ohio 45229-3039, USA. grift0@chmcc.org
Abstract:
We have identified a mammalian homologue of yeast Ump1p by searching for similar proteins in human and mouse expressed sequence tag (EST) databases. Ump1p is an accessory protein that is required for normal proteasome assembly in yeast (1). A mammalian homologue, which we refer to as "proteassemblin," is a constituent of proteasome assembly intermediates (preproteasomes), but not fully assembled 20S proteasomes, as is Ump1p in yeast. We also provide evidence that proteassemblin is a constituent of pre-immunoproteasomes that contain the precursor of the interferon-gamma-inducible subunit LMP2. By analogy with Ump1p, we hypothesize that proteassemblin is required for normal mammalian proteasome assembly.
Related Concept Videos
Protein Complex Assembly
Many viruses self-assemble into a fully functional unit using the infected host cell to...
The Proteasome
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
The Spindle Assembly Checkpoint
Many proteins function together to control the spindle assembly checkpoint. Mutations affecting these proteins may allow cells to proceed into anaphase prematurely, resulting in the...
The Unfolded Protein Response
The Proteasome
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3 (ubiquitin...
The Proteasome Structure
The proteasome is an...

