Optineurin (OPTN) is a multifunctional protein encoded by the *OPTN* gene, initially identified for its role in primary open-angle glaucoma and amyotrophic lateral sclerosis (ALS). It participates in diverse cellular processes, including vesicle trafficking, autophagy, inflammation, and NF-κB signaling. OPTN interacts with proteins like TBK1. huntingtin, and myosin VI, and acts as an autophagy receptor by binding ubiquitinated substrates (e.g., damaged mitochondria) via its ubiquitin-binding domain. Dysfunctional OPTN is linked to neurodegenerative diseases, glaucoma, and cancers.
OPTN antibodies are essential tools for studying its expression, localization, and interactions. They are widely used in Western blotting, immunohistochemistry, and immunofluorescence to investigate OPTN’s role in autophagy (e.g., in ALS models) or inflammation (e.g., in NF-κB pathway regulation). Commercial antibodies often target specific domains (e.g., N-terminal or coiled-coil regions) to distinguish functional isoforms or disease-associated mutants (e.g., E478G in ALS). Validation is critical, as OPTN’s low abundance and post-translational modifications (e.g., phosphorylation by TBK1) can affect antibody specificity. Researchers also employ OPTN antibodies to explore its diagnostic potential in glaucoma or cancer, where altered expression correlates with disease progression. Challenges include cross-reactivity with homologous proteins like NRP1. necessitating careful experimental controls.