Aquaporins (AQPs), commonly known as water channels, play integral roles in facilitating the movement of solutes (urea/water) across biological cell membranes. In this study, AQPs in Squalus acanthias was investigated, a species renowned for its unique urea retention abilities. Through a combination of mRNA expression analysis using quantitative PCR and immunohistochemistry, the tissue-specific expression patterns were characterized and the subcellular localization of AQP10C1 and AQP10C2. The results revealed distinct roles for these AQPs: AQP10C1 exhibited predominant expression in gill tissue, suggesting its crucial involvement in osmoregulation processes. Conversely, AQP10C2 demonstrated varying expressions in kidney and intestine cells, hinting at its potential contribution to urea transport and homeostasis mechanisms. These findings shed light on the intricate functions of urea transport and homeostasis in marine organisms, thereby advancing our understanding of osmoregulation processes. Furthermore, this research holds promise for elucidating the functions of vertebrate AQPs.
