Pannexin1 (Panx1) is a transmembrane channel-forming protein belonging to the pannexin family, which comprises three members (Panx1. Panx2. Panx3). Initially identified in 2003. Panx1 is the most studied and forms large-pore channels permeable to ions and small molecules (≤1 kDa), including ATP. It plays critical roles in intercellular signaling, inflammation, apoptosis, and pathological processes such as epilepsy, stroke, and cancer. Panx1 channels are regulated by post-translational modifications, including caspase cleavage during apoptosis, and interact with purinergic receptors to mediate extracellular ATP release.
Panx1-specific antibodies are essential tools for studying its expression, localization, and function. These antibodies typically target unique epitopes in Panx1’s extracellular loops or intracellular domains. For example, antibodies against the C-terminal region (e.g., amino acids 350-426) are widely used in Western blotting and immunohistochemistry to detect Panx1 in tissues like brain, immune cells, and epithelia. However, Panx1 antibody specificity remains a topic of debate due to reported cross-reactivity with Panx2 or other proteins in some studies. Validation via knockout controls or peptide blocking is strongly recommended. Recent advancements include phospho-specific antibodies to study Panx1’s regulatory modifications. Commercially available monoclonal and polyclonal Panx1 antibodies (e.g., from Sigma, Abcam) have facilitated research into its pathophysiological roles, though discrepancies in staining patterns across studies highlight the need for standardized protocols.