Car13, a member of the carbonic anhydrase (CA) gene family, encodes an enzyme that catalyzes the conversion of carbon dioxide to carbonic acid, thereby participating in various physiological processes such as acid-base balance, respiration, and fluid formation [1,2,3,4]. It is involved in pathways related to ion homeostasis and may have a role in metabolic processes in different tissues [1,2]. Genetic models like knockout mouse models can be valuable in studying its function.

During mammalian inner ear development, Car13 is one of the cytosolic isozymes expressed at higher levels [1]. In the mouse digestive system, it shows relatively high expression in certain tissues, suggesting its potential involvement in physiological processes beyond the typical CA-catalyzed reactions [2]. In the mouse harderian gland, Car13 has a high mRNA expression level [3]. In the neonatal mouse uterus, Car13 mRNA is detected in both endometrial epithelia and stroma, and its function may be related to endometrial gland development as treatment with a CA inhibitor decreased the number of endometrial glands [4].

In conclusion, Car13 plays essential roles in the development and function of multiple tissues, including the inner ear, digestive system, harderian gland, and neonatal uterus. Studies using models like neonatal mice treated with a CA inhibitor have revealed its significance in endometrial gland development. These findings contribute to understanding the biological functions of Car13 and its potential implications in related physiological and pathological conditions.