title: Association of MUC-1 and SPGL-1 with low-density microdomain in T-lymphocytes: a preliminary note.
abstract: Two mucin-type glycoproteins, MUC-1 and P-selectin glycoprotein ligand-1 (PSGL-1), and glycosphingolipids (GSLs), expressed in human T-cell line HUT78, were highly enriched in low-density buoyant fraction (termed "GEM"), together with CD45, Yes, Fyn, and lck(56). Enrichment of MUC-1, PSGL-1 and GSLs, together with these signal transducer molecules in low-density membrane fraction was observable when fraction was prepared from cells either in nonionic detergent Brij 58 or in hypertonic alkaline conditions (500 mM Na(2)CO(3)). On pretreatment of cells with cholesterol-binding reagent methyl beta-cyclodextrin, levels of MUC-1 and PSGL-1 together with the above signal transducers in GEM was greatly reduced, and they were translocated into high-density membrane fraction. Similar association of lck(56), Yes, Fyn, and cSrc together with MUC-1 was also found in GEM fraction of mouse T-cell lymphoma EL4 cells expressing MUC-1 through transfection of its gene. These findings indicate the presence of another glycosyl cluster ("glycocluster"), in addition to the previously well-established GSL cluster organized with signal transducer molecules in GEM fraction, and its possible functional role in T-cells.
authors.affiliation: Division of Biomembrane Research, Pacific Northwest Research Institute, 720 Broadway, Seattle, WA 98122, USA.
authors.forename: K
authors.initials: K
authors.lastname: Handa
authors.forename: F
authors.initials: F
authors.lastname: Jacobs
authors.forename: B M
authors.initials: BM
authors.lastname: Longenecker
authors.forename: S I
authors.initials: SI
authors.lastname: Hakomori
mesh_terms: D000818:Animals; D002460:Cell Line; D002462:Cell Membrane / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D002499:Centrifugation, Density Gradient; D003505:Cyclodextrins / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D006028:Glycosphingolipids / Q000378:metabolism; D006031:Glycosylation; D006801:Humans; D017493:Leukocyte Common Antigens / Q000032:analysis / Q000378:metabolism; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck) / Q000032:analysis / Q000378:metabolism; D016399:Lymphoma, T-Cell / Q000378:metabolism; D046911:Macromolecular Substances; D008562:Membrane Glycoproteins / Q000378:metabolism*; D021962:Membrane Microdomains / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D018396:Mucin-1 / Q000378:metabolism*; D021381:Protein Transport / Q000187:drug effects; D011518:Proto-Oncogene Proteins / Q000032:analysis / Q000378:metabolism; D051076:Proto-Oncogene Proteins c-fyn; D051575:Proto-Oncogene Proteins c-yes; D015398:Signal Transduction / Q000502:physiology; D013347:Subcellular Fractions / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism; D013601:T-Lymphocytes / Q000737:chemistry / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D019061:src-Family Kinases
chemical_list: D003505:Cyclodextrins; D006028:Glycosphingolipids; D046911:Macromolecular Substances; D008562:Membrane Glycoproteins; D018396:Mucin-1; C084882:P-selectin ligand protein; D011518:Proto-Oncogene Proteins; C494957:FYN protein, human; C494960:Fyn protein, mouse; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck); D051076:Proto-Oncogene Proteins c-fyn; D051575:Proto-Oncogene Proteins c-yes; C496639:Yes1 protein, mouse; D019061:src-Family Kinases; D017493:Leukocyte Common Antigens