protein_function: Receptor for hyaluronic acid (HA). Mediates cell-celland cell-matrix interactions through its affinity for HA, andpossibly also through its affinity for other ligands such asosteopontin, collagens, and matrix metalloproteinases (MMPs).Adhesion with HA plays an important role in cell migration, tumorgrowth and progression. In cancer cells, may play an importantrole in invadopodia formation. Also involved in lymphocyteactivation, recirculation and homing, and in hematopoiesis (Bysimilarity). Receptor for LGALS9; the interaction enhances bindingof SMAD3 to the FOXP3 promoter, leading to up-regulation of FOXP3expression and increased induced regulatory T (iTreg) cellstability and suppressive function (PubMed:25065622)..
CD44 is an integral cell membrane glycoprotein with a postulated role in matrix adhesion lymphocyte activation and lymph node homing. It is contains 19 exons spanning 50 kb of genomic DNA. In humans, the CD44 antigen is encoded by the CD44 gene on Chromosome 11. The protein encoded by this gene is a cell-surface glycoprotein involved in cell-cell interactions, cell adhesion and migration. It is a receptor for hyaluronic acid (HA) and can also interact with other ligands, such as osteopontin, collagens, and matrix metalloproteinases (MMPs). Transcripts for this gene undergo complex alternative splicing that results in many functionally distinct isoforms, however, the full length nature of some of these variants has not been determined. Alternative splicing is the basis for the structural and functional diversity of this protein, and may be related to tumor metastasis.
