RILPL2 (Rab interacting lysosomal protein like 2) is an adaptor protein that regulates cellular trafficking and ciliogenesis through interactions with phosphorylated Rab GTPases and the motor protein Myosin Va. RILPL2 binds with high affinity to LRRK2-phosphorylated Rab8A and Rab10 via a specialized X-cap recognition motif involving dual arginine residues (R130 and R132) that interact with phosphorylated threonine residues 1. This interaction redistributes Myosin Va to pericentriolar regions, and RILPL2 overexpression blocks ciliogenesis in retinal pigment epithelium cells 2. In migrating cells, RILPL2 functions as an adaptor protein facilitating Myosin Va-mediated transport of Rab10-CAV1-marked intraluminal vesicles to migrasomes, enabling intercellular communication and wound healing responses 3. Clinically, RILPL2 shows tumor-suppressive functions in breast cancer, where overexpression inhibits proliferation and metastasis via the TUBB3/PTEN pathway and reverses chemoresistance 4. In non-small cell lung cancer, reduced RILPL2 expression correlates with worse overall survival and lower CD4+ and CD8+ T cell infiltration, suggesting RILPL2 regulates tumor immunity 56. RILPL2 has also been identified as a hub gene in fibromyalgia immune-related networks 7.