Detailed N-glycan analysis of mannose receptor purified from murine spleen indicates tissue specific sialylation.
The mannose receptor (MR) is a heavily glycosylated endocytic receptor that recognises both mannosylated and sulphated ligands through its C-type lectin domains (CTLDs) and cysteine-rich (CR) domain, respectively. It is widely expressed among different tissues and by certain cell types in vivo. Our previous study suggested that the glycosylation, especially terminal sialylation, regulated the functional specificities of MR. In the current investigation, the distribution of MR among various mouse tissues was studied and the N-linked glycosylation of spleen MR was analysed. Our results showed that spleen expressed the most abundant MR, consistent with its wide distribution in different cell types in this organ. Spleen MR was heterogeneously N-glycosylated. The majority of the glycans were sialylated in the alpha2 --> 6-linkage and both Neu5Ac and Neu5Gc sialic acids were detected. Most glycans were bi-antennary (74%) with approximately 22% tri-antennary and most were core fucosylated (68%). About 13% contained alpha-galactose. In the lung, MR exhibited more terminal sialic acids in the alpha2 --> 3- rather than in the alpha2 --> 6-configuration. Our study provides a profile of MR N-linked glycosylation that will facilitate our understanding of their physiological role on MR biology in vivo.
Glycobiology Institute, Biochemistry Department, University of Oxford, South Parks Road, OX1, 3QU, United Kingdom. ysu@swmail.sw.org
Yunpeng
Y
Su
Louise
L
Royle
Catherine M
CM
Radcliffe
David J
DJ
Harvey
Raymond A
RA
Dwek
Luisa
L
Martinez-Pomares
Pauline M
PM
Rudd
D000818:Animals; D002240:Carbohydrate Sequence; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D006031:Glycosylation; D037181:Lectins, C-Type / Q000737:chemistry / Q000378:metabolism*; D000090323:Mannose Receptor; D037241:Mannose-Binding Lectins / Q000737:chemistry / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D015394:Molecular Structure; D011134:Polysaccharides / Q000737:chemistry / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000737:chemistry / Q000378:metabolism*; D012794:Sialic Acids / Q000737:chemistry / Q000378:metabolism*; D013154:Spleen / Q000378:metabolism*
D037181:Lectins, C-Type; D000090323:Mannose Receptor; D037241:Mannose-Binding Lectins; D011134:Polysaccharides; D011956:Receptors, Cell Surface; D012794:Sialic Acids