Syndecan-4 (SDC4)

Syndecan-4 is a ubiquitously expressed, type I transmembrane heparan sulfate proteoglycan, belonging to the syndecan family of cell surface receptors[1][4]. It consists of an extracellular domain modified with heparan sulfate chains, a single-pass transmembrane domain, and a short intracellular cytoplasmic domain that interacts with cytoskeletal and signaling proteins[3]. Syndecan-4 functions both as a co-receptor for heparin-binding growth factors (such as FGFs, VEGFs, and PDGFs) and as an independent signaling molecule modulating cell adhesion, migration, mechanotransduction, and endocytosis[4]. It is the only syndecan family member consistently enriched at focal adhesions, linking the extracellular matrix to the actin cytoskeleton via integrin interactions and regulating signaling events such as PKC activation[1][4]. Syndecan-4 plays essential roles in processes like wound healing, angiogenesis, arterial development, and placental invasion, and is implicated in the pathogenesis of cancer, inflammatory diseases, preeclampsia, and cardiovascular disease[1][4][5]. No approved drugs directly target syndecan-4, but its functions and expression are considered relevant for therapeutic and biomarker development.

Other names

Syndecan-4SDC4SYND4amphiglycanryudocanAmphiglycanRyudocan core proteinsyndecan proteoglycan 4syndecan 4 (amphiglycan, ryudocan)ryudocan amphiglycan

Co-receptor for fibroblast growth factor (FGF) signaling; Activation of protein kinase C (PKC); Modulation of integrin function and focal adhesion signaling; Regulation of growth factor availability and receptor signaling.