PSMB10

PSMB10, also known as MECL-1, is a gene that encodes the proteasome subunit beta type-10, a component of the 20S core particle of the proteasome. In humans, PSMB10 is one of the immunoproteasome subunit genes and is specifically associated with the immunoproteasome that forms in response to immune signals.

The PSMB10 gene is located within the major histocompatibility complex (MHC) region on chromosome 6p21.3. Its product is synthesized as a propeptide that is processed to its mature form and then incorporated into the proteasome's beta rings. In cells of the immune system, particularly antigen-presenting cells such as dendritic cells, macrophages, and B cells, expression of PSMB10 is upregulated by interferon-gamma, enabling the formation of immunoproteasomes.

Functionally, MECL-1 (PSMB10) replaces one of the constitutive beta subunits in the proteasome to form the immunoproteasome. This substitution alters proteolytic activities and peptide generation, generally favoring production of peptides with hydrophobic or basic C- termini that bind efficiently to MHC class I molecules. Through these changes, MECL-1 contributes to the efficiency and quality of antigen presentation to CD8+ T cells.

Clinical and research relevance centers on the role of the immunoproteasome in immune responses and inflammatory processes. Altered expression or function of MECL-1 can influence peptide repertoires and immune surveillance, with implications for infection, autoimmunity, and cancer. Further study continues to elucidate its precise contributions within diverse immunological contexts.