TY - JOUR
T1 - The role of glycosylation in secretion and membrane expression of immunoglobulins M and A
AU - Sitia, Roberto
AU - Rubartelli, Anna
AU - Hämmerling, Ulrich
PY - 1984
Y1 - 1984
N2 - The role of glycosylation in membrane expression and secretion of IgM and IgA was investigated in murine lymphoma and hybridoma cell lines, derived from 1.29 tumor, which synthesize IgM or IgA with identical variable regions. Tunicamycin, a selective inhibitor of N-linked glycosylation, prevented the membrane expression of both isotypes, as demonstrated by immunofluorescence, radioiodination and endogenous labeling experiments. Selective immunoprecipitation and immunochemical analysis of membrane, intracellular and secreted molecules permitted us to determine the amount of membrane heavy chain externalized in the presence or absence of tunicamycin. Id 150 and Id 43, two I.29-derived hybridomas secreting IgA and IgM respectively, were differently affected by tunicamycin. While secretion of IgM was inhibited to > 95%, no inhibition of secretion of non-glycosylated IgA could be detected in Id 150 cells. These results indicate that different requirements for glycosylation exist in the biosynthetic pathways of immunoglobulin isotypes, and suggest that distinct intracellular transport systems may operate for membrane and secreted α-chains.
AB - The role of glycosylation in membrane expression and secretion of IgM and IgA was investigated in murine lymphoma and hybridoma cell lines, derived from 1.29 tumor, which synthesize IgM or IgA with identical variable regions. Tunicamycin, a selective inhibitor of N-linked glycosylation, prevented the membrane expression of both isotypes, as demonstrated by immunofluorescence, radioiodination and endogenous labeling experiments. Selective immunoprecipitation and immunochemical analysis of membrane, intracellular and secreted molecules permitted us to determine the amount of membrane heavy chain externalized in the presence or absence of tunicamycin. Id 150 and Id 43, two I.29-derived hybridomas secreting IgA and IgM respectively, were differently affected by tunicamycin. While secretion of IgM was inhibited to > 95%, no inhibition of secretion of non-glycosylated IgA could be detected in Id 150 cells. These results indicate that different requirements for glycosylation exist in the biosynthetic pathways of immunoglobulin isotypes, and suggest that distinct intracellular transport systems may operate for membrane and secreted α-chains.
UR - http://www.scopus.com/inward/record.url?scp=0021220824&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0021220824&partnerID=8YFLogxK
U2 - 10.1016/0161-5890(84)90023-3
DO - 10.1016/0161-5890(84)90023-3
M3 - Article
C2 - 6749140
AN - SCOPUS:0021220824
VL - 21
SP - 709
EP - 719
JO - Molecular Immunology
JF - Molecular Immunology
SN - 0161-5890
IS - 8
ER -