Psmb2 Protein is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
| Full Name | Proteasome Subunit Beta Type-2 |
|---|---|
| Gene | [PSMB2](/genes/psmb2) |
| UniProt ID | [P49721](https://www.uniprot.org/uniprot/P49721) |
| PDB ID | [5MX3](https://www.ebi.ac.uk/pdbe/5MX3) |
| Molecular Weight | 22.8 kDa |
| EC Number | 3.4.25.1 |
| Subcellular Localization | Cytoplasm, Nucleus |
| Protein Family | Proteasome beta subunit family (Psmb2/beta-2) |
| Aliases | LMP10, d beta, beta-2 |
PSMB2 (Proteasome Subunit Beta Type-2) is a critical catalytic subunit of the 20S proteasome core particle, providing the trypsin-like proteolytic activity essential for protein degradation within the ubiquitin-proteasome system (UPS)[1]. PSMB2 is constitutively expressed in most tissues, including the brain, where it plays a fundamental role in maintaining cellular proteostasis by degrading oxidized, misfolded, and regulatory proteins[2].
The proteasome is a 28-subunit protease complex organized as a 20S core particle (CP) flanked by one or two 19S regulatory particles. The 20S CP consists of four heptameric rings: two outer α-rings (PSMA1-7) that form the gate for substrate entry, and two inner β-rings (PSMB1-7) that contain the proteolytic active sites[3].
PSMB2 adopts the classic proteasome β-subunit fold:
The crystal structure (PDB: 5MX3) shows PSMB2 adopts the typical β-subunit conformation with the catalytic threonine positioned at the interface between the two β-rings[4].
The 20S proteasome contains:
PSMB2 specifically cleaves after basic residues (lysine, arginine) in the substrate sequence[5].
PSMB2 provides trypsin-like proteolytic activity within the 20S proteasome:
PSMB2 and the proteasome are affected in AD:
The study of Psmb2 Protein has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
Tanaka K. The proteasome: Overview of structure and function. Proc Jpn Acad Ser B Phys Biol Sci. 2020. ↩︎
Dikic I. Proteasome and autophagy: The cellular degradation systems. Cold Spring Harb Perspect Biol. 2020. ↩︎
Glickman MH, et al. The regulatory particle of the eukaryotic 26S proteasome. Adv Exp Med Biol. 2021. ↩︎
Harshbarger W, et al. Crystal structure of the human 20S proteasome at 2.75 Å resolution. Sci Rep. 2020. ↩︎
Kisselev AF, et al. The effects of subunit composition and mechanism of the proteasome. J Biol Chem. 2019. ↩︎
Oddo S. The ubiquitin-proteasome system in Alzheimer's disease. J Cell Mol Med. 2022. ↩︎
Pal A, et al. Proteasome dysfunction in Alzheimer's disease: New therapeutic targets. Neurotherapeutics. 2021. ↩︎