Prolectin, a glycan-binding receptor on dividing B cells in germinal centers.
Prolectin, a previously undescribed glycan-binding receptor, has been identified by re-screening of the human genome for genes encoding proteins containing potential C-type carbohydrate-recognition domains. Glycan array analysis revealed that the carbohydrate-recognition domain in the extracellular domain of the receptor binds glycans with terminal alpha-linked mannose or fucose residues. Prolectin expressed in fibroblasts is found at the cell surface, but unlike many glycan-binding receptors it does not mediate endocytosis of a neoglycoprotein ligand. However, compared with other known glycan-binding receptors, the receptor contains an unusually large intracellular domain that consists of multiple sequence motifs, including phosphorylated tyrosine residues, that allow it to interact with signaling molecules such as Grb2. Immunohistochemistry has been used to demonstrate that prolectin is expressed on a specialized population of proliferating B cells in germinal centers. Thus, this novel receptor has the potential to function in carbohydrate-mediated communication between cells in the germinal center.
Division of Molecular Biosciences, Department of Life Sciences, Imperial College, London SW7 2AZ, United Kingdom.
Sarah A
SA
Graham
Sabine A F
SA
Jégouzo
Sheng
S
Yan
Alex S
AS
Powlesland
Jacob P
JP
Brady
Maureen E
ME
Taylor
Kurt
K
Drickamer
D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D001402:B-Lymphocytes / Q000502:physiology*; D001667:Binding, Competitive / Q000502:physiology; D002450:Cell Communication / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D003593:Cytoplasm / Q000378:metabolism; D005110:Extracellular Space / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology / Q000502:physiology; D018858:Germinal Center / Q000166:cytology / Q000502:physiology*; D006801:Humans; D007150:Immunohistochemistry; D037181:Lectins, C-Type / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D011134:Polysaccharides / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D021381:Protein Transport / Q000502:physiology; D011817:Rabbits; D051381:Rats; D011956:Receptors, Cell Surface / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology
D000906:Antibodies; C578707:CLEC17A protein, human; D037181:Lectins, C-Type; D011134:Polysaccharides; D011956:Receptors, Cell Surface