RABL2A encodes a small GTPase that plays essential roles in male fertility and cilia function through its regulation of intracellular protein transport 1. The protein localizes to sperm tails and is highly conserved between mouse and human, where it functions in sperm intra-flagellar transport and tail assembly 1. RABL2A operates through GTP-regulated binding to specific effector proteins involved in cilia development and function 2. Mechanistically, RABL2A interacts with proteins like CCDC34 in its GTP-bound state and can modulate MAPK signaling pathways including p38 and JNK 3. The gene shows preferential expression compared to its paralog RABL2B in human tissues, particularly in brain and placenta 4. Disease relevance includes male infertility, where genetic variants in RABL2A are associated with oligoasthenospermia 1, and ciliopathies, where deleterious alleles cause infertility, growth defects, heterotaxia, polydactyly, and neural tube defects 2. Additionally, RABL2A downregulation is observed in pancreatic cancer and associated with poor survival 5, while the protein has been implicated in sorafenib resistance in hepatocellular carcinoma 3. These findings establish RABL2A as a critical regulator of ciliary function with significant implications for fertility and cancer prognosis.