RAB34 is a small GTPase that functions as a key regulator of intracellular membrane trafficking and vesicular transport. As a member of the Rab GTPase superfamily, RAB34 cycles between inactive GDP-bound and active GTP-bound states to recruit effector proteins responsible for vesicle formation, movement, and fusion 1. RAB34 has multiple cellular roles: it transports proteins involved in lysosomal redistribution to the peri-Golgi region 1, mediates phagosome maturation and fusion with lysosomes during pathogen engulfment 2, and regulates adipocyte lipid metabolism through Golgi-mediated adiponectin trafficking and lipid droplet function 3. RAB34 is essential for intracellular ciliogenesis, particularly the early steps of ciliary vesicle trafficking and docking to centrioles 4, with its N-terminal LPQ sequence critical for this function 4. In craniofacial development, RAB34 controls both ciliogenesis-mediated Hedgehog signaling and type I collagen trafficking 5. Pathogenic RAB34 variants cause orofaciodigital syndrome 20 through impaired cilium assembly 6. RAB34 is also oncogenic in multiple cancers: it promotes colorectal cancer progression via MEK/ERK signaling 7, correlates with glioma aggressiveness and poor prognosis 89, and drives breast cancer metastasis through integrin β3-mediated cell migration and invasion 10.