Arl13a, a member of the Arf-like (Arl) family of small GTP-binding proteins, is a close paralog to Arl13b. The Arl family proteins regulate numerous cellular functions and are crucial for cilia structure and signaling [1].

In zebrafish, during early cell division and gastrulation, arl13a is widely expressed, and its encoded protein localizes to microtubules in ciliated and dividing cells. However, by 2 days post-fertilization (dpf), its expression is downregulated and restricted to craniofacial structures, indicating it may not function in the zebrafish retina as arl13b does [1]. In cheetahs, mutations in ARL13A, along with three other genes (DEFB116, CFAP119, and NT5DC4), have been linked to male fertility and immune deficiencies, suggesting pseudogenization of ARL13A may contribute to reproductive and health challenges in this species [2,3].

In summary, Arl13a is involved in early zebrafish development and may have a role in craniofacial development. In cheetahs, its mutation seems to be associated with male fertility and immune-related issues. Research on Arl13a in these genetic models helps to understand its diverse biological functions and its implications in specific species-related health problems.