TY - JOUR
T1 - In situ trans ligands of CD22 identified by glycan-protein photocross-linking-enabled proteomics
AU - Ramya, T. N.C.
AU - Weerapana, Eranthie
AU - Liao, Lujian
AU - Zeng, Ying
AU - Tateno, Hiroaki
AU - Liao, Liang
AU - Yates, John R.
AU - Cravatt, Benjamin F.
AU - Paulson, James C.
PY - 2010/6
Y1 - 2010/6
N2 - CD22, a regulator of B-cell signaling, is a siglec that recognizes the sequence NeuAcα2-6Gal on glycoprotein glycans as ligands. CD22 interactions with glycoproteins on the same cell (in cis) and apposing cells (in trans) modulate its activity in B-cell receptor signaling. Although CD22 predominantly recognizes neighboring CD22 molecules as cis ligands on B-cells, little is known about the trans ligands on apposing cells. We conducted a proteomics scale study to identify candidate trans ligands of CD22 on B-cells by UV photocross-linking CD22-Fc chimera bound to B-cell glycoproteins engineered to carry sialic acids with a 9-aryl azide moiety. Using mass spectrometry-based quantitative proteomics to analyze the cross-linked products, 27 glycoproteins were identified as candidate trans ligands. Next, CD22 expressed on the surface of one cell was photocross-linked to glycoproteins on apposing B-cells followed by immunochemical analysis of the products with antibodies to the candidate ligands. Of the many candidate ligands, only the B-cell receptor IgM was found to be a major in situ trans ligand of CD22 that is selectively redistributed to the site of cell contact upon interaction with CD22 on the apposing cell.
AB - CD22, a regulator of B-cell signaling, is a siglec that recognizes the sequence NeuAcα2-6Gal on glycoprotein glycans as ligands. CD22 interactions with glycoproteins on the same cell (in cis) and apposing cells (in trans) modulate its activity in B-cell receptor signaling. Although CD22 predominantly recognizes neighboring CD22 molecules as cis ligands on B-cells, little is known about the trans ligands on apposing cells. We conducted a proteomics scale study to identify candidate trans ligands of CD22 on B-cells by UV photocross-linking CD22-Fc chimera bound to B-cell glycoproteins engineered to carry sialic acids with a 9-aryl azide moiety. Using mass spectrometry-based quantitative proteomics to analyze the cross-linked products, 27 glycoproteins were identified as candidate trans ligands. Next, CD22 expressed on the surface of one cell was photocross-linked to glycoproteins on apposing B-cells followed by immunochemical analysis of the products with antibodies to the candidate ligands. Of the many candidate ligands, only the B-cell receptor IgM was found to be a major in situ trans ligand of CD22 that is selectively redistributed to the site of cell contact upon interaction with CD22 on the apposing cell.
UR - https://www.scopus.com/pages/publications/77953142478
U2 - 10.1074/mcp.M900461-MCP200
DO - 10.1074/mcp.M900461-MCP200
M3 - 文章
C2 - 20172905
AN - SCOPUS:77953142478
SN - 1535-9476
VL - 9
SP - 1339
EP - 1351
JO - Molecular and Cellular Proteomics
JF - Molecular and Cellular Proteomics
IS - 6
ER -