GOLIM4 (Golgi Integral Membrane Protein 4) functions as a critical scaffold protein that coordinates multiple aspects of Golgi-dependent cellular processes. The protein plays a central role in endosome-to-Golgi protein trafficking, serving as a scaffold that recruits ATP2C1 and GOLPH3 to coordinate calcium-dependent cargo loading, Golgi membrane bending, and vesicle scission 1. GOLIM4 is essential for the late endosome-to-Golgi retrieval pathway, working in conjunction with the AP-5 adaptor complex and retromer to transport proteins like the cation-independent mannose 6-phosphate receptor back to the Golgi 2. Beyond its trafficking functions, GOLIM4 maintains intracellular manganese homeostasis by binding excess manganese in the Golgi lumen, which triggers lysosomal degradation of the protein 1. The protein exists in multiple splice variants, with the long isoform (GOLIM4-L) containing exon-7 being particularly important in cancer progression through its interaction with RAB26 and regulation of vesicle-mediated transport 3. GOLIM4 also modulates cell motility by regulating post-Golgi trafficking of focal adhesion components like Talin 1 4. The gene is frequently amplified in various cancers, where it drives secretory addiction and tumor progression 15.