FUNCTION: Also acts as the receptor for echovirus 7 and related viruses (echoviruses 13, 21, 29 and 33).
SUBUNIT: Monomer (major form) and non-disulfide-linked, covalent homodimer (minor form).
PTM: The Ser/Thr-rich domain is heavily O-glycosylated.
SIMILARITY: Contains 4 Sushi (CCP/SCR) domains.
SUBCELLULAR LOCATION: Attached to the membrane by a GPI-anchor (isoform 2).
TISSUE SPECIFICITY: Expressed on the plasma membranes of all cell types that are in intimate contact with plasma complement proteins. It is also found on the surfaces of epithelial cells lining extracellular compartments, and variants of the molecule are present in body fluids and in extracellular matrix.