EF-hand, extracellular calcium-binding (EC) motif, found in secreted modular calcium-binding protein SMOC-1, SMOC-2, and similar proteins
SMOC proteins corresponds to a group matricellular proteins that are involved in direct or indirect modulation of growth factor signaling pathways and play diverse roles in physiological processes involving extensive tissue remodeling, migration, proliferation, and angiogenesis. They may mediate intercellular signaling and cell type-specific differentiation during gonad and reproductive tract development. SMOC-1 is localized in basement membranes. Its mutations have been found to be associated with individuals with Warrdenburg Anopthalmia Syndrome. SMOC-2 is ubiquitously expressed and is involved in angiogenesis and the regulation of cell cycle progression. It enhances the angiogenic effect of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF). It has also been implicated in generalized vitiligo. SMOC proteins consist of a follistatin-like (FS) domain, two thyroglobulin-like (TY) domains, a novel domain conserved only in SMOC proteins, and an extracellular calcium-binding (EC) domain with two EF-hand calcium-binding motifs.
Jiyao W et al.(2023). "The conserved domain database in 2023.",