Commentary: Taurine as a central osmoprotectant in marine molluscs - Roles in osmoregulation, oxidative balance and...

Taurine, a β-amino sulfonic acid, is among the most abundant free amino acids in marine molluscs and functions as a dominant osmoprotectant critical for maintaining cellular homeostasis under fluctuating salinity. Beyond its osmoregulatory role, taurine exerts multifunctional cytoprotective, antioxidant, and immunomodulatory effects, positioning it as a key molecule in molluscan stress physiology. This commentary synthesises our current understanding of taurine dynamics in marine molluscs, highlighting recent advances in taurine transport, metabolism, and stress-responsive regulation. Particular attention is given to the taurine transporter (TauT) and its function in coordinating uptake and efflux during osmotic challenges, as well as the emerging evidence linking taurine to antioxidant defence and innate immunity. By integrating findings from molecular, biochemical, and cellular studies, this commentary underscores taurine as a multifunctional molecule fundamental to molluscan stress tolerance and identifies promising directions for future research, including omics-driven analyses of taurine regulatory pathways and their ecological relevance in rapidly changing marine ecosystems.