Based on limited published evidence, SACK1B is a scaffolding protein that anchors casein kinase 1 (CK1) and functions in EGFR signaling pathways, activating downstream RAS/MAPK and PI3K/AKT/TOR cascades. SACK1B shares structural homology with SACK1G/FAM83G, which plays a central role in WNT signaling through CK1α binding 1. The conserved scaffold-anchor domain is critical for CK1 interaction, and mutations disrupting this domain impair kinase binding and signaling activation.