The lymphatic vasculature forms a second circulatory system that drains extracellular fluid from the tissues and provides an exclusive environment in which immune cells can encounter and respond to foreign antigen. Recently a number of interesting molecules have been identified that may be exploited as markers for lymphatic endothelium, including the hyaluronan receptor LYVE1, PALE, VEGFR3, podoplanin. LYVE1 has been identified as a major receptor for HA (extracellular matrix glycosaminoglycan hyaluronan) on the lymph vessel wall. The deduced amino acid sequence of LYVE1 predicts a 322-residue type I integral membrane polypeptide 41% similar to the CD44 HA receptor with a 212-residue extracellular domain containing a single Link module the prototypic HA binding domain of the Link protein superfamily. Like CD44, the LYVE1 molecule binds both soluble and immobilized HA. However, unlike CD44, the LYVE1 molecule colocalizes with HA on the luminal face of the lymph vessel wall and is completely absent from blood vessels. Hence, LYVE1 is the first lymph-specific HA receptor to be characterized and is a uniquely powerful marker for lymph vessels themselves.
Function:
Ligand-specific transporter trafficking between intracellular organelles (TGN) and the plasma membrane. Plays a role in autocrine regulation of cell growth mediated by growth regulators containing cell surface retention sequence binding (CRS). May act as an hyaluronan (HA) transporter, either mediating its uptake for catabolism within lymphatic endothelial cells themselves, or its transport into the lumen of afferent lymphatic vessels for subsequent re-uptake and degradation in lymph nodes.
Subunit:
Homodimer; disulfide-linked. Interacts with PDGFB and IGFBP3. Forms a transient ternary complex with PDGFB and PDGFRB in TGN.
Subcellular Location:
Membrane; Single-pass type I membrane protein. Note=Localized to the plasma membrane and in vesicles near extranuclear membranes which may represent trans-Golgi network (TGN) and endosomes/prelysosomeal compartments. Undergoes ligand-dependent internalization and recycling at the cell surface.
Tissue Specificity:
Restricted to tissues or cell lines expressing erythroid characters.
Post-translational modifications:
O-glycosylated.
Similarity:
Contains 1 Link domain.
SWISS:
Q9Y5Y7
Gene ID:
114332
Database links:
Entrez Gene: 10894 Human
Entrez Gene: 114332 Mouse
Omim: 605702 Human
SwissProt: Q9Y5Y7 Human
SwissProt: Q8SHC0 Mouse
Unigee: 246769 Human
Unigene: 655332 Human
Unigene: 396078 Mouse
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