ARL4A (ADP-ribosylation factor-like 4A) is a small GTPase that primarily functions in regulating cell migration and cytoskeletal remodeling through multiple membrane-associated mechanisms. The protein cycles between GDP-bound inactive and GTP-bound active forms, though it uniquely acts independently of canonical GTPase regulation 1. ARL4A promotes cell migration by interacting with the guidance receptor Robo1 in a GTP-dependent manner, leading to Cdc42 activation and enhanced cell motility 2. At the Golgi apparatus, ARL4A complexes with golgin GCC185 to maintain Golgi structure and facilitate endosome-to-Golgi transport by promoting GCC185-CLASP interactions 3. The protein also regulates EGFR degradation by binding to ESCRT-II component VPS36, prolonging EGFR ubiquitination and delaying lysosomal transport 4. Additionally, ARL4A complexes with ELMO proteins to promote actin cytoskeleton remodeling and membrane ruffling through DOCK180-Rac signaling 5. Protein stability is regulated by fibronectin-induced phosphorylation at S143, which promotes HYPK chaperone binding and stable plasma membrane recruitment 1. Clinically, ARL4A expression is altered in various pathological conditions including sepsis-induced lung injury, nonobstructive azoospermia, and thrombosis in fracture patients 678.