Siglecs--the major subfamily of I-type lectins.
Animal glycan-recognizing proteins can be broadly classified into two groups-lectins (which typically contain an evolutionarily conserved carbohydrate-recognition domain [CRD]) and sulfated glycosaminoglycan (SGAG)-binding proteins (which appear to have evolved by convergent evolution). Proteins other than antibodies and T-cell receptors that mediate glycan recognition via immunoglobulin (Ig)-like domains are called "I-type lectins." The major homologous subfamily of I-type lectins with sialic acid (Sia)-binding properties and characteristic amino-terminal structural features are called the "Siglecs" (Sia-recognizing Ig-superfamily lectins). The Siglecs can be divided into two groups: an evolutionarily conserved subgroup (Siglecs-1, -2, and -4) and a CD33/Siglec-3-related subgroup (Siglecs-3 and -5-13 in primates), which appear to be rapidly evolving. This article provides an overview of historical and current information about the Siglecs.
Varki
Ajit
A
Research Center for Glycoscience, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568, Japan. varkiadmin@ucsd.edu
Angata
Takashi
T
D000818:Animals; D002450:Cell Communication / Q000502:physiology*; D019143:Evolution, Molecular; D006801:Humans; D037102:Lectins / Q000378:metabolism*; D011134:Polysaccharides / Q000378:metabolism*; D011485:Protein Binding / Q000502:physiology; D063265:Sialic Acid Binding Immunoglobulin-like Lectins; D012794:Sialic Acids / Q000378:metabolism*
D037102:Lectins; D011134:Polysaccharides; D063265:Sialic Acid Binding Immunoglobulin-like Lectins; D012794:Sialic Acids