JAB1 (Jun activation domain-binding protein 1), also known as COPS5 or CSN5. is a multifunctional protein initially identified as a coactivator of the AP-1 transcription factor. It serves as a key component of the COP9 signalosome (CSN) complex, which regulates protein degradation via the ubiquitin-proteasome system and modulates cellular processes like DNA repair, cell cycle progression, and signal transduction. JAB1 interacts with diverse signaling molecules, including p27Kip1 (a cell cycle inhibitor), stabilizing their degradation and promoting cell proliferation. Its dysregulation is linked to cancer, neurodegenerative diseases, and inflammatory conditions, making it a research focus in pathophysiology.
JAB1 antibodies are essential tools for studying its expression, localization, and interactions in cells. They enable techniques such as Western blotting, immunohistochemistry, and co-immunoprecipitation to explore JAB1's role in disease mechanisms. For example, elevated JAB1 levels in tumors correlate with poor prognosis, and antibodies help validate its overexpression in clinical samples. Additionally, JAB1 antibodies aid in investigating post-translational modifications and CSN complex assembly. Their specificity is critical for distinguishing JAB1 from homologous proteins and elucidating its dual roles in both oncogenic and tumor-suppressive contexts. Research using these antibodies continues to uncover therapeutic targets and biomarkers for diseases associated with JAB1 dysregulation.