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Proteasome subunit alpha type-5

Function

Component of the 20S core proteasome complex involved in the proteolytic degradation of most intracellular proteins. This complex plays numerous essential roles within the cell by associating with different regulatory particles. Associated with two 19S regulatory particles, forms the 26S proteasome and thus participates in the ATP-dependent degradation of ubiquitinated proteins. The 26S proteasome plays a key role in the maintenance of protein homeostasis by removing misfolded or damaged proteins that could impair cellular functions, and by removing proteins whose functions are no longer required. Associated with the PA200 or PA28, the 20S proteasome mediates ubiquitin-independent protein degradation. This type of proteolysis is required in several pathways including spermatogenesis (20S-PA200 complex) or generation of a subset of MHC class I-presented antigenic peptides (20S-PA28 complex).

Sequence similarities

Belongs to the peptidase T1A family.

Tissue specificity

Expressed in fetal brain (at protein level).

Cellular localization

  • Cytoplasm
  • Nucleus
  • Translocated from the cytoplasm into the nucleus following interaction with AKIRIN2, which bridges the proteasome with the nuclear import receptor IPO9.

Alternative names

Proteasome subunit alpha type-5, Macropain zeta chain, Multicatalytic endopeptidase complex zeta chain, Proteasome subunit alpha-5, Proteasome zeta chain, alpha-5, PSMA5

Target type

Proteins

Primary research area

Oncology

Molecular weight

26411Da