EVOLUTION OF A FAMILY OF RECEPTORS CONTAINING MULTIPLE C-TYPE CARBOHYDRATE-RECOGNITION DOMAINS

The identification of a novel receptor on mouse endothelial cells and chondrocytes brings to four the number of proteins containing multiple C-type carbohydrate-recognition domains in a single polypeptide (Wu e t al., 1996). The prototype of this group is the macrophage mannose re ceptor, which mediates endocytosis of glycoconjugates with terminal ma nnose, N-acetylglucosamine or fucose residues (Taylor et al., 1990; Ha rris et al., 1992). The other previously described members of the fami ly are a widely distributed receptor for phospholipases A(2) (Ishizaki et al., 1994; Higashino et al., 1994; Lambeau et al., 1994, 1995), an d a receptor named DEC-205 found on thymic epithelium and dendritic ce lls, and believed to be involved in uptake of antigens for processing (Jiang et al., 1995). Functional studies on the new member of the fami ly have not yet been reported, but it is likely that it too mediates e ndocytosis, possibly of glycoconjugates.