ERC1 (ELKS/RAB6-interacting/CAST family member 1) is a multifunctional scaffold protein with distinct roles in immune signaling and cell motility. In the immune pathway, ERC1 functions as a regulatory subunit of the IKK complex that recruits IκBα to facilitate canonical NF-κB signal transduction 1. The dengue virus NS5 protein antagonizes this function by degrading ERC1, thereby suppressing proinflammatory cytokine production 1. ERC1 also drives cell migration through assembly of plasma membrane-associated platforms at the leading edge of motile cells. It forms a functional complex with liprin-α1 and LL5 proteins that stabilizes protrusive activity and coordinates actin-adhesion dynamics required for tumor cell invasion 2. ERC1 assembles into dynamic liquid-phase condensates with flexible dimer architecture, concentrating migration-relevant partners at the cell periphery 3. The biophysical properties of these condensates are essential for motility; altering their composition or structure impairs cell migration 4. The ERC1-LL5β interaction is particularly critical for maintaining plasma membrane platforms and invadopodia formation 5. Additionally, ERC1 participates in centrosome organization and vesicle trafficking, interacting with RAB effector proteins RABEP2 for endosomal-Golgi transport and Hedgehog signaling 6. ERC1 variants are associated with lung squamous cell carcinoma susceptibility in African Americans 7.