The PSMD11 antibody is a crucial tool for studying the 26S proteasome regulatory particle, specifically targeting the PSMD11 subunit (also known as S9 or Rpn6) within the 19S complex. The 26S proteasome is a multi-subunit protease responsible for ubiquitin-dependent protein degradation, essential for maintaining cellular homeostasis, regulating cell cycle progression, and degrading misfolded proteins. PSMD11. as part of the 19S regulatory cap, plays a structural and functional role in substrate recognition, deubiquitination, and ATP-dependent unfolding of target proteins. Antibodies against PSMD11 are widely used in techniques like Western blotting, immunohistochemistry, and immunoprecipitation to investigate proteasome composition, dynamics, and dysfunction. Research highlights its involvement in diseases such as cancer, where proteasome activity is often dysregulated, and neurodegenerative disorders linked to protein aggregation. PSMD11 antibodies also aid in studying the effects of proteasome inhibitors, potential therapeutics for multiple myeloma. Validation of these antibodies includes verifying specificity through knockdown models or recombinant protein assays. Understanding PSMD11's role via antibody-based approaches provides insights into proteasomal regulation, cellular stress responses, and therapeutic targeting of proteostasis pathways.