Pannexins (Panx) are proteins homologous to the invertebrate gap junction 
proteins called innexins (Inx) and are traditionally described as transmembrane 
channels connecting the intracellular and extracellular compartments. Three 
distinct Panx paralogs (Panx1, Panx2 and Panx3) have been identified in 
vertebrates but previous reports on Panx expression and functionality focused 
primarily on Panx1 and Panx3 proteins. Several gene expression studies reported 
that Panx2 transcript is largely restricted to the central nervous system (CNS) 
hence suggesting that Panx2 might serve an important role in the CNS. However, 
the lack of suitable antibodies prevented the creation of a comprehensive map of 
Panx2 protein expression and Panx2 protein localization profile is currently 
mostly inferred from the distribution of its transcript. In this study, we 
characterized novel commercial monoclonal antibodies and surveyed Panx2 
expression and distribution at the mRNA and protein level by real-time qPCR, 
Western blotting and immunofluorescence. Panx2 protein levels were readily 
detected in every tissue examined, even when transcriptional analysis predicted 
very low Panx2 protein expression. Furthermore, our results indicate that Panx2 
transcriptional activity is a poor predictor of Panx2 protein abundance and does 
not correlate with Panx2 protein levels. Despite showing disproportionately high 
transcript levels, the CNS expressed less Panx2 protein than any other tissues 
analyzed. Additionally, we showed that Panx2 protein does not localize at the 
plasma membrane like other gap junction proteins but remains confined within 
cytoplasmic compartments. Overall, our results demonstrate that the endogenous 
expression of Panx2 protein is not restricted to the CNS and is more ubiquitous 
than initially predicted.