Taxonomic group: fungi / Ascomycota
(Phylum: Ascomycota)
Organ / tissue: cell wall
NCBI PubMed ID: 22331432Publication DOI: 10.1128/IAI.06308-11Journal NLM ID: 0246127Publisher: American Society for Microbiology
Correspondence: Inaba K <kayo
lif.kyoto-u.ac.jp>
Institutions: Department of Animal Development and Physiology, Graduate School of Biostudies, Kyoto University, Kyoto, Japan, CREST, Kyoto University, Kyoto, Japan, Department of Infection and Host Defense, Tohoku Pharmaceutical University, Komatsushima, Japan, Research Center for Medical Glycoscience, National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central Umezono, Ibaraki, Japan
C-type lectin SIGNR1 directly recognizes Candida albicans and zymosan and has been considered to share properties of polysaccharide recognition with human DC-SIGN (hDC-SIGN). However, the precise specificity of SIGNR1 and the difference from that of hDC-SIGN remain to be elucidated. We prepared soluble forms of SIGNR1 and hDC-SIGN and conducted experiments to examine their respective specificities. Soluble SIGNR1 (sSIGNR1) bound several types of live C. albicans clinical isolate strains in an EDTA-sensitive manner. Inhibition analyses of sSIGNR1 binding by glycans from various yeast strains demonstrated that SIGNR1 preferentially recognizes N-glycan α-mannose side chains in Candida mannoproteins, as reported in hDC-SIGN. Unlike shDC-SIGN, however, sSIGNR1 recognized not only Saccharomyces cerevisiae, but also C. albicans J-1012 glycan, even after α-mannosidase treatment that leaves only β1,2-mannose-capped α-mannose side chains. In addition, glycomicroarray analyses showed that sSIGNR1 binds mannans from C. albicans and S. cerevisiae but does not recognize Lewis(a/b/x/y) antigen polysaccharides as in shDC-SIGN. Consistent with these results, RAW264.7 cells expressing hDC-SIGN in which the carbohydrate recognition domain (CRD) was replaced with that of SIGNR1 (RAW-chimera) produced comparable amounts of interleukin 10 (IL-10) in response to glycans from C. albicans and S. cerevisiae, but those expressing hDC-SIGN produced less IL-10 in response to S. cerevisiae than C. albicans. Furthermore, RAW-hDC-SIGN cells remarkably reduced IL-10 production after α-mannosidase treatment compared with RAW-chimera cells. These results indicate that SIGNR1 recognizes C. albicans/yeast through a specificity partly distinct from that of its homologue hDC-SIGN.
lectin, Candida albicans, DC-SIGN, mannoprotein
Structure type: structural motif or average structure
Location inside paper: Fig.1, A, right bottom corner structure
Aglycon: (->4)ID 45997-protein
Compound class: mannan
Contained glycoepitopes: IEDB_130701,IEDB_140116,IEDB_141793,IEDB_141828,IEDB_144983,IEDB_152206,IEDB_153220,IEDB_153762,IEDB_153763,IEDB_76933,IEDB_983930,SB_198,SB_44,SB_67,SB_72
Methods: DNA techniques, ELISA, biological assays, enzymatic digestion, extraction, cell growth, Fehling treatment
Related record ID(s): 45846, 45847, 45848, 45849, 45850, 45851, 45852, 45853, 45997
NCBI Taxonomy refs (TaxIDs): 4932Reference(s) to other database(s): GTC:G55317BB
Show glycosyltransferases
There is only one chemically distinct structure:
Found 
report error