CD44
Cell-surface receptor that plays a role in cell-cell interactions, cell adhesion and migration, helping them to sense and respond to changes in the tissue microenvironment. Participates thereby in a wide variety of cellular functions including the activation, recirculation and homing of T-lymphocytes, hematopoiesis, inflammation and response to bacterial infection. Engages, through its ectodomain, extracellular matrix components such as hyaluronan/HA, collagen, growth factors, cytokines or proteases and serves as a platform for signal transduction by assembling, via its cytoplasmic domain, protein complexes containing receptor kinases and membrane proteases. Such effectors include PKN2, the RhoGTPases RAC1 and RHOA, Rho-kinases and phospholipase C that coordinate signaling pathways promoting calcium mobilization and actin-mediated cytoskeleton reorganization essential for cell migration and adhesion. Isoform 10 (epithelial isoform) is expressed by cells of epithelium and highly expressed by carcinomas. Expression is repressed in neuroblastoma cells. 19 alternatively spliced human isoforms have been reported. Note: This description may include information from UniProtKB.
Protein type: Cell adhesion; Membrane protein, integral; Motility/polarity/chemotaxis; Receptor, misc.
Molecular Function: cargo receptor activity; channel regulator activity; cytokine binding; cytokine receptor activity; epidermal growth factor receptor binding; hyaluronic acid binding; phosphoprotein binding; protein binding; protein kinase binding; transmembrane signaling receptor activity; type II transforming growth factor beta receptor binding
Biological Process: branching involved in prostate gland morphogenesis; branching involved in ureteric bud morphogenesis; cell adhesion; cell migration; cellular response to fibroblast growth factor stimulus; hyaluronan catabolic process; inflammatory response; macrophage fusion; monocyte aggregation; negative regulation of apoptotic process; negative regulation of CD4-positive, alpha-beta T cell proliferation; negative regulation of cysteine-type endopeptidase activity involved in apoptotic process; negative regulation of DNA damage response, signal transduction by p53 class mediator; negative regulation of inflammatory response; negative regulation of intrinsic apoptotic signaling pathway in response to DNA damage by p53 class mediator; negative regulation of mature B cell apoptotic process; negative regulation of regulatory T cell differentiation; neuron projection development; positive regulation of adaptive immune response; positive regulation of ERK1 and ERK2 cascade; positive regulation of gene expression; positive regulation of heterotypic cell-cell adhesion; positive regulation of monocyte aggregation; positive regulation of neutrophil apoptotic process; positive regulation of peptidyl-serine phosphorylation; positive regulation of peptidyl-tyrosine phosphorylation; receptor-mediated endocytosis; regulation of cell growth; regulation of lamellipodium morphogenesis; T cell activation; Wnt signaling pathway; wound healing involved in inflammatory response; wound healing, spreading of cells
