EFR3A (EFR3 homolog A) is a peripheral plasma membrane protein that serves as a critical scaffolding component for localizing phosphatidylinositol 4-kinase (PI4KA) complexes to the plasma membrane 12. The protein functions as a membrane-anchoring component within a heterotrimeric complex containing PI4KA, TTC7, and FAM126 proteins, where it undergoes a disorder-to-order transition upon binding and directly interacts with both TTC7B and FAM126A 12. This complex regulates phosphatidylinositol 4-phosphate (PtdIns4P) synthesis, which is essential for maintaining plasma membrane lipid composition and asymmetry 1. EFR3A also participates in membrane raft organization through its interaction with flotillin-2, affecting plasma membrane order and cellular signaling pathways including EGFR and phospholipase C gamma 3. Disease relevance includes associations with autism spectrum disorders, where rare deleterious mutations in EFR3A are significantly more common in cases than controls 4. The protein is also implicated in neuronal development, as its mRNA is stabilized by RNA-binding protein Rbms1, which is required for proper neuronal differentiation and radial migration during neocortical development 5. Additionally, EFR3A mutations have been linked to various human disorders including neurological, cardiovascular, and neoplastic conditions 6.