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1.
Profiling of carbohydrate structures on cell membranes has been difficult to perform because of the complexity and the variations
of such structures on cell surface glycans. This study presents a novel method for rapid profiling of cell surface glycans
for terminal N-acetyllactosamines (Galβ1-(3)4GlcNAc-R) that are uncapped, capped with sialic acid as SA-Galβ1-(3)4GlcNAc-R, or with α1,3galactosyls
as the α-gal epitope- Galα1-3Galβ1-(3)4GlcNAc-R. This method includes two enzymatic reactions: (1) Terminal sialic acid is
removed by neuraminidase, and (2) α-gal epitopes are synthesized on the exposed N-acetyllactosamines by α1,3galactosyltransferase. Existing and de novo synthesized α-gal epitopes on cells are quantified by a modification of radioimmunoassay designated as “ELISA inhibition
assay,” which measures binding of the monoclonal anti-Gal antibody M86 to α-gal epitopes. This binding is proportional to
the number of cell surface α-gal epitopes. The amount of free M86 antibody molecules remaining in the solution is determined
by ELISA using synthetic α-gal epitopes linked to albumin as solid phase antigen. The number of α-gal epitopes on cells is
estimated by comparing binding curves of M86 incubated with the assayed cells, at various concentrations of the cells, with
the binding of M86 to rabbit red cells expressing 2 × 106 α-gal epitopes/cell. We could demonstrate large variations in the number of sialic acid capped N-acetyllactosamines, α-gal epitopes and uncapped N-acetyllactosamines on different mammalian red blood cells, and on nucleated cells originating from a given tissue in various
species. This method may be useful for rapid identification of changes in glycosylation patterns in cells subjected to various
treatments, or in various states of differentiation. 相似文献
2.
Daisei Miyamoto Takao Ueno Sachiko Takashima Kazuhide Ohta Toshio Miyawaki Takashi Suzuki Yasuo Suzuki 《Glycoconjugate journal》1997,14(3):379-388
A new monoclonal antibody (TU-1) directed against the Galα1-4Galβ1-4Glc residue of the Gb3Cer/CD77 antigen was prepared by
the hybridoma technique following immunization of mice with an emulsion composed of monophosphoryl lipid A, trehalose dimycolate,
and Gb3Cer isolated from porcine erythrocytes. TU-1 showed reactivity towards Gb3Cer and lyso-Gb3Cer (Galα1-4Galβ1-4Glcβ1-1′Sph),
although the reactivity towards lyso-Gb3Cer was about 10-fold lower than that to Gb3Cer. But it did not react with other structurally-related
glycolipids, such as LacCer (Galβ1-4Glcβ1-1′Cer), Gg3Cer, Gg4Cer, Gb4Cer (GalNAcβ1-3Galα1-4Galβ1-4Glcβ1-1′Cer), galactosylparagloboside
(Galα1-3Galβ1-4GlcNAcβ1-3Galβ1-4Glcβ1-1′Cer), sulfatide (HSO3-3Galβ1-1′Cer), other gangliosides (GM3, GM2, GM1a, GD1a and
GT1b), or P1 antigen (Galα1-4Galβ1-4GlcNAcβ1-3Galβ1-4Glcβ1-1′Cer) among neutral glycolipids prepared from P1 phenotype red
blood cells. Furthermore, TU-1 reacted with viable lymphoma cells, such as human Burkitt lymphoma cell line, Daudi, and Epstein-Barr
virus (EBV)-transformed B cells by the immunofluorescence method, and also with germinal centre B cells in human tonsil and
vessel endothelial cells in human thymus histochemically. These results indicate that TU-1 is a monoclonal antibody directed
against Gb3Cer/CD77 antigen and can be utilized as a diagnostic reagent for Burkitt's lymphoma and also for detection of the
blood group Pk antigen in glycolipid extracts of erythrocytes. Abbreviations: ATL, adult T-cell leukaemia; BSA, bovine serum
albumin; Cer, ceramide; DPPC, L-α-dipalmitoylphosphatidylcholine; EBV, Epstein-Barr virus; FCS, fetal calf serum; GalCer,
Galβ1-1′Cer; GlcCer, Glcβ1-1′Cer; LacCer, Galβ1-4Glcβ1-1′Cer; Gb3Cer, Galα1-4Galβ1-4Glcβ1-1′Cer; Iyso-Gb3Cer, Galα1-4Galβ1-4Glc1-1′Sph;
Gb4Cer, GalNAcβ1-3Galα1-4Galβ1-4Glc1-1′Cer; galactosylparagloboside, Galα1-3Galβ1-4GlcNAcβ1-3Galβ1-4Glcβ1-1′Cer; Gg3Cer, GalNAcβ1-4Galβ1-4Glcβ1-1′Cer;
Gg4Cer, Galβ1-3GalNAcβ1-4Galβ1-4Glcβ1-1′Cer; GM3, Neu5Acα2-3Galβ1-4Glcβ1-1′Cer; GM2, GalNAcβ1-4(Neu5Acα2-3) Galβ1-4Glcβ1-1′Cer;
GM1a, Galβ1-3GalNAcβ1-4(Neu5Acα2-3)Galβ1-4Glcβ1-1′Cer; GD1a, Neu5Acα2-3Galβ1-3GalNAcβ1-4(Neu5Acα2-3)Galβ1-4Glcβ1-1′Cer; GD1b,
Galβ1-3GalNAcβ1-4(Neu5Acα2-8Neu5Acα2-3)Galβ1-4Glcβ1-1′Cer; GT1b, Neu5Acα2-3Galβ1-3GalNAcβ1-4(Neu5Acα2-8Neu5Acα2-3) Galβ1-4Glcβ1-1′Cer;
HRP, horseradish peroxidase; LDH, lactate dehydrogenase; MAb, monoclonal antibody; MPL, monophosphoryl lipid A; P1 antigen,
Galα1-4Galβ1-4GlcNAcβ1-3Galβ1-4Glcβ1-1′Cer; PVP, polyvinylpyrolidone; Sph, sphingosine; sulfatide, HSO3-Galβ1-1′Cer; TDM,
trehalose dimycolate; TLC, thin-layer chromatography
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
3.
Rare polyagglutinable NOR erythrocytes contain unusual globoside extention products terminating with a Galα1-4GalNAcβ1-3Gal-
unit. This trisaccharide epitope is recognized by recently characterized antibodies naturally occurring in most human sera
(Duk et al., Glycobiology, 15, 109, 2005). These antibodies represent two major types of fine specificity. All these antibodies are most strongly inhibited by Galα1-4GalNAcβ1-3Gal
(NOR-tri), and weakly by Galα1-4Gal. However, the type 1 antibodies are strongly inhibited by Galα1-4Galβ1-3Gal-R and weakly
by Galα1-4GalNAc, while the type 2 antibodies show the opposite reactivities with these two oligosaccharides. Similar antibodies
have now been found in horse, rabbit and pig sera. The antibodies were purified from animal sera by affinity chromatography
on Galα1-4GalNAcβ1-3Gal-human serum albumin(HSA)-Sepharose 4B conjugate. The specificity of the antibodies was determined
by binding to ELISA plates coated with several α-galactosylated oligosaccharide-polyacrylamide (PAA) or -HSA conjugates and
by inhibition with synthetic oligosaccharides. The purified antibodies bound specifically to conjugates containing NOR-tri.
The inhibition of binding showed that the animal sera also contain two types of anti-NOR antibodies: type 2 was found in the
horse serum, and a mixture of both types was present in rabbit and pig serum. These results indicate that anti-NOR, a new
and distinct kind of anti-αGal antibody, are present in animal sera and show similar specificties and diversity as their counterparts
found in human sera. 相似文献
4.
Previous studies on the carbohydrate specificities of Erythrina cristagalli lectin (ECL) were mainly limited to analyzing the binding of oligo-antennary Galβ1→4GlcNAc (II). In this report, a wider range of recognition factors of ECL toward known mammalian ligands and glycans were examined by
enzyme-linked lectinosorbent and inhibition assays, using natural polyvalent glycotopes, and a glycan array assay. From the
results, it is shown that GalNAc was an active ligand, but its polyvalent structural units, in contrast to those of Gal, were
poor inhibitors. Among soluble natural glycans tested for 50% molecular mass inhibition, Streptococcus pneumoniae type 14 capsular polysaccharide of polyvalent II was the most potent inhibitor; it was 2.1 × 104, 3.9 × 103 and 2.4 × 103 more active than Gal, tri-antennary II and monomeric II, respectively. Most type II-containing glycoproteins were also potent inhibitors, indicating that special polyvalent II and Galβ1-related structures play critically important roles in lectin binding. Mapping all information available, it can
be concluded that: [a] Galβ1→4GlcNAc (II) and some Galβ1-related oligosaccharides, rather than GalNAc-related oligosaccharides, are the core structures for lectin
binding; [b] their polyvalent II forms within macromolecules are a potent recognition force for ECL, while II monomer and oligo-antennary II forms play only a limited role in binding; [c] the shape of the lectin binding domains may correspond to a cavity type with
Galβ1→4GlcNAc as the core binding site with additional one to four sugars subsites, and is most complementary to a linear
trisaccharide, Galβ1→4GlcNAcβ1→6Gal. These analyses should facilitate the understanding of the binding function of ECL.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
5.
Jeschke U Karsten U Wiest I Schulze S Kuhn C Friese K Walzel H 《Histochemistry and cell biology》2006,126(4):437-444
Galectin-1 (gal-1), a member of the mammalian β-galactoside-binding proteins, recognizes preferentially Galβ1-4GlcNAc sequences of several cell surface oligosaccharides. We demonstrate histochemically that the lectin recognizes appropriate glycotopes on the syncytiotrophoblast and extravillous trophoblast layer from second trimester human placenta and on BeWo chorion carcinoma cells. Gal-1 binding to BeWo cells was diminished by the Thomsen–Friedreich (TF)-disaccharide (Galβ1-3GalNAc-) conjugated to polyacrylamide (TF–PAA). Gal-1 also inhibited BeWo cell proliferation in a concentration-dependent manner. Similar antiproliferative effects were also observed with an anti-TF monoclonal antibody (mAb, A78-G/A7). Therefore, we conclude that ligation of Galβ1-4GlcNAc and Galβ1-3GalNAc epitopes on BeWo cells may have regulatory effects on cell proliferation. 相似文献
6.
Matrix-assisted laser desorption/ionization quadrupole ion trap time-of-flight mass spectrometry (MALDI-QIT-TOF MS) was used
to analyze three pyridylamino (PA)-fucosyloligosaccharides isolated from human milk: lacto-N-fucopentaose (LNFP) I [Fucα1-2Galβ1-3GlcNAcβ1-3Galβ1-4Glc-PA],
LNFP II [Galβ1-3(Fucα1-4)GlcNAcβ1-3Galβ1-4Glc-PA], and LNFP III [Galβ1-4(Fucα1-3)GlcNAcβ1-3Galβ1-4Glc-PA]. These oligosaccharides
are linkage isomers. MALDI-QIT-TOF MS provides MSn spectra, which we used to characterize these PA-oligosaccharides. MS/MS/MS analysis of the non-reducing end tri-saccharide
ions generated by MS/MS was able to distinguish these oligosaccharide isomers. The MALDI-QIT-TOF MS is a very convenient and
rapid method, therefore, it would be useful for high throughput structural analyses of various types of pyridylaminated oligosaccharide
isomers. 相似文献
7.
E.P. Smorodin O.A. Kurtenkov B.L. Sergeyev G.V. Pazynina N.V. Bovin 《Glycoconjugate journal》2003,20(2):83-89
The TF, Tn, and SiaTn glycotopes are frequently expressed in cancer-associated mucins. Antibodies to these glycotopes were
found in human serum. A set of polyacrylamide (PAA)—based glycoconjugates was applied to the direct and competitive enzyme-linked
immunosorbent assays (ELISA) to characterize the specificity of serum IgG antibodies. The anti-TF, -Tn and -SiaTn IgG were
affinity purified from serum of cancer patients and characterized using PAA-conjugates and free saccharides. The anti-TF and
-Tn antibodies were shown to be specific. The anti-TF IgG bound both Galβ1-3GalNAcα- and Galβ1-3GalNAcβ-PAA, the latter was
three-four times more effective inhibitor of antibody binding. The anti-Tn IgG reacted only with GalNAcα-PAA. The anti-SiaTn
IgG cross-reacted with Tn-PAA but SiaTn-PAA was five-six times more effective inhibitor in a competitive assay. The IC50 values for PAA-conjugates with the corresponding antibodies typically ranged from 2 to 5 × 10−8 M. The antibodies display a low specificity to mucin-type glycoconjugates in comparison with PAA-conjugates as was shown
for mucins isolated from human malignant tumor tissues, ovine submaxillary mucin (OSM) and asialo-OSM. The unusual IgG-antibody
specificity to GalNAcβ and GalNAcβ1-3GalNAcβ ligands was found in human serum. Published in 2004.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
8.
The transforming growth factor-beta (TGF-β) 1 is a mediator of extracellular matrix (ECM) gene expression in mesangial cells
and the development of diabetic glomerulopathy. Here, we investigate the effects of TGF-β1 on laminin γ1 and fibronectin polypeptide
expression and cell survival in mouse mesangial cells (MES-13). TGF-β1 (10 ng/ml) stimulates laminin-γ1 and fibronectin expression
~two-fold in a time-dependent manner (0–48 h). TGF-β1 treatment also retards laminin-γ1 mobility on SDS-gels, and tunicamycin,
an inhibitor of the N-linked glycosylation, blocks the mobility shift. TGF-β1 increases the binding of laminin γ1 to WGA-agarose
and the binding is abolished by tunicamycin suggesting that laminin γ1 is modified by N-linked glycosylation. TGF-β1 also
elevates fibronectin glycosylation but its mobility is not altered. The degradation of laminin γ1 and fibronectin proteins
is reduced by their glycosylation. In addition, TGF-β1 enhances mesangial cell viability and metabolic activities initially
(0–24 h); however, eventually leads to cell death (24–48 h). TGF-β1 elevates pro-apoptotic caspase-3 activity and decrease
cell cycle progression factor cyclin D1 expression, which parallels cell death. These results indicate that TGF-β1 plays an
important role in ECM expression, protein glycosylation and demise of mesangial cells in the diabetic glomerular mesangium.
(Mol Cell Biochem 278: 165–175, 2005) 相似文献
9.
The relationship of N-linked glycosylation and heavy chain-binding protein association with the secretion of glycoproteins 总被引:20,自引:6,他引:14 下载免费PDF全文
《The Journal of cell biology》1987,105(6):2665-2674
The relationship of N-linked glycosylation and association with heavy chain binding protein (BiP) to the secretion of Factor VIII (FVIII), von Willebrand Factor (vWF), and tissue plasminogen activator (tPA) was studied in Chinese hamster ovary (CHO) cells. FVIII has a heavily glycosylated region containing 20 clustered potential N-linked glycosylation sites. A significant proportion of FVIII was detected in a stable complex with BiP and not secreted. Deletion of the heavily glycosylated region resulted in reduced association with BiP and more efficient secretion. Tunicamycin treatment of cells producing this deleted form of FVIII resulted in stable association of unglycosylated FVIII with BiP and inhibition of efficient secretion. vWF contains 17 potential N-linked glycosylation sites scattered throughout the molecule. vWF was transiently associated with BiP and efficiently secreted demonstrating that CHO cells are competent to secrete a highly glycosylated protein. tPA, which has three utilized N-linked glycosylation sites, exhibited low level association with BiP and was efficiently secreted. Disruption of N-linked glycosylation of tPA by either site-directed mutagenesis or tunicamycin treatment resulted in reduced levels of secretion and increased association with BiP. This effect was enhanced by high levels of tPA expression. The glycosylation state and extent of association with BiP could be correlated with secretion efficiency. 相似文献
10.
Binding of carbohydrate ligand by human C-reactive protein (CRP), in both native form and structurally deviated form (neoCRP
or mCRP), was investigated using galactose-6-phosphate (Gal6P)- and Galβ3GalNAc-containing bovine serum albumin (BSA) derivatives.
To this end, we synthesized glycosides of Gal6P and Galβ3GalNAc that can potentially generate a terminal aldehyde group. ω-Aldehydo
glycosides were then conjugated to BSA via reductive amination. Using these neoglycoproteins, we showed that: (1) Gal6P-BSA and Galβ3GalNAc-BSA bound to both forms
of CRP, the former with or without calcium and the latter only in the absence of calcium; (2) phosphate-containing ligands
can be bound with or without calcium, but the binding is much stronger in the presence of calcium than in the absence, underscoring
the importance of direct coordination of phosphate to two calcium ions observed in the X-ray structure of phosphorylcholine
(PC)–CRP complex; (3) cross-inhibition studies further corroborated the hypothesis that binding sites of PC and sugar are
contiguous; (4) while PC-BSA bound to the native CRP over a wide pH range of 4.5 to 9, all the carbohydrate ligands and protamine-BSA
(poly-cation-based ligand) exhibited optimal binding at around pH 6 to 6.5; and (5) ligand-binding conformation of mCRP appears
to be more fragile than that of the native CRP in the acidic media (pH < 6). 相似文献
11.
Stephen Henry Per-Ake Jovall Sohbat Ghardashkhani Anders Elmgren Tommy Martinsson Goran Larson Bo Samuelsson 《Glycoconjugate journal》1997,14(2):209-223
Total nonacid glycosphingolipids were isolated from small intestine mucosal scrapings of a red cell blood group O Le(a-b-)
nonsecretor cadaver. Glycolipids were extracted and fractionated into five fractions based on chromatographic and immunostaining
properties. These glycolipid fractions were then analysed by thin-layer chromatography for Lewis activity with antibodies
reactive to the type 1 precursor (Lec), H type 1 (Led), Lea and Leb epitopes. Fractions were structurally characterized by
mass spectrometry (EI-MS and EI-MS/MS-TOF) and proton NMR spectroscopy. EI-MS/MS-TOF allowed for the identification of trace
substances in fractions containing several other glycolipid species. Consistent with the red cell phenotype, large amounts
of lactotetraosylceramide (Lec-4) were detected. Inconsistent with the red cell phenotype, small quantities of Lea-5, H-5-1
and Leb-6 glycolipids were immunochemically and structurally identified in the small intestine of this individual. By EI-MS/MS-TOF
several large glycolipids with 9 and 10 sugar residues were also identified. The extensive carbohydrate chain elongation seen
in this individual with a Lewis negative nonsecretor phenotype supports the concept that Lewis and Secretor blood group fucosylation
may be a mechanism to control type 1 glycoconjugate chain extension. Abbreviations: FUT1, H gene; FUT2, Secretor gene, (gene
bank accession no. U17894); FUT3, Lewis gene or Fuc-TIII gene, (gene bank accession no. X53578); FUT5, Fuc-TV gene; [Imm]+,
immonium ion; Lea-5, Galβ1-3(Fucα1-4)GlcNAcβ1-3Galβ1-4Glcβ1-1Cer; Leb-6, Fucα1-2Galβ1-3(Fucα1-4)GlcNAcβ1-3Galβ1-4Glcβ1-1Cer;
Lec-4, Galβ1-3GlcNAcβ1-3Galβ1-4Glcβ1-1Cer; Led or H-5-1, Fucα1-2Galβ1-3GlcNAcβ1-3Galβ1-4Glcβ1-1Cer; Lex-5, Galβ1-4(Fucα1-3)GlcNAcβ1-3Galβ1-4Glcβ1-1Cer;
MAb, monoclonal antibody; MS, mass spectrometry; CID, collision-induced dissociation; EI, electron impact ionisation; MS/MS-TOF,
tandem mass spectrometry using a time-of-flight mass spectrometer as the second mass spectrometer: m/Cz, mass-to-charge ratio;
NMR, nuclear magnetic resonance; PCR, polymerase chain reaction; RFLP, restriction fragment length polymorphism; TLC, (high
performance) thin layer chromatography. Saccharide types are abbreviated to Hex for hexose, HexNAc for N-acetylhexosamine
and dHex for deoxyhexose (fucose). Ceramide is abbreviated to Cer, and ceramide types are abbreviated to d for dihydroxy and
t for trihydroxy base, n for non-hydroxy and h for hydroxy fatty acids
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
12.
Glycosylation is one of the most important post-translational modifications. It is clear that the single step of β-1,4-galactosylation
is performed by a family of β-1,4-galactosyltransferases (β-1,4-GalTs), and that each member of this family may play a distinct
role in different tissues and cells. β-1,4-GalT I and V are involved in the biosynthesis of N-linked oligosaccharides. In
the present study, Real-time PCR revealed that the β-1,4-GalT I and V mRNAs reached peaks at 2 w after sciatic nerve crush.
In situ hybridization showed that at 1 d after sciatic nerve crush, the expression levels of β-1,4-GalT I and V mRNAs were
strong at the crush site, and decreased gradually from crush site to the distal segments. In addition, combined in situ hybridization
for β1,4-GalT I and V mRNAs and immunohistochemistry for S100 showed that β1,4-GalT I and V mRNAs were mainly located in Schwann
cells. Lectin blot showed that the expression of Galβ1,4GlcNAc group increased at 6 h immediately, reached a peak at 12 h
and remained elevated up to 4 w after sciatic nerve crush. In conclusion, β1,4-GalT I and V might play important roles in
the regeneration of the injuried sciatic nerve, and upregulation of Galβ1,4GlcNAc group might be correlated with the process
of the sciatic nerve injury. 相似文献
13.
Johannes Muthing 《Glycoconjugate journal》1997,14(2):241-248
The gangliosides GM1b, GalNAc-GM1b and GD1α are typical compounds of concanavalin A stimulated splenic T lymphoblasts of CBA/J
inbred mice. Their structural characterization has been described in previous studies. The intention of this work was the
comparative TLC immunostaining analysis of the glycosphingolipid composition of lectin stimulated splenic T lymphoblasts obtained
from six genetically different inbred mouse strains. The strains examined were AKR, BALB/c, C57BL/6, CBA/J, DBA/2 and WHT/Ht,
which are commonly used for biochemical and immunological studies. The neutral glycosphingolipid GgOse4Cer, the precursor
for GM1b-type gangliosides, was expressed by all six strains investigated. AKR, C57BL/6 and DBA/2 showed high and BALB/c,
CBA/J and WHT/Ht diminished expression in T lymphoblasts, based on single cell calculation. The gangliosides GM1b and GalNAc-GM1b,
elongation products of GgOse4Cer, displayed strain-specific differences in their intensities, which were found to correlate
with the intensities of GgOse4Cer expression of the same strains. Concerning sialic acid substitution of gangliosides, GM1b
and GalNAc-GM1b predominantly carry N-acetylneuraminic acid, whereas choleragenoid receptors GM1a and Gal-GalNAc-GM1b, which
are also expressed by all six strains, are characterized by dominance of N-glycolylneuraminic acid. Two highly polar gangliosides, designated with X and Y, which have not been previously recognized
in murine lymphoid tissue, were detected by positive anti-GalNAc-GM1b antibody and choleragenoid binding, respectively. Both
gangliosides were restricted to AKR, DBA/2 and C57BL/6 mice. The other three strains BALB/c, CBA/J and WHT/Ht are lacking
these structures. In summary, the GM1b-type pathway is quite active in all six strains analysed in this study. Strain-specific
genetic variations in T lymphoblast gangliosides were observed with the occurrence of gangliosides X and Y. This study and
data from other groups strongly indicate for GM1b-type gangliosides a functional association with T cell activation and leukocyte
mediated reactions. Abbreviations: ConA, concanavalin A; GSL(s), glycosphingolipid(s); HPTLC, high-performance thin-layer
chromatography; NeuAc, N-acetylneuraminic acid; NeuGc, N-glycolylneuraminic acid. The designation of the following glycosphingolipids
follows the IUPAC-IUB recommendations (1977) [48] and the ganglioside nomenclature system of Svennerholm [49] for GM1a-type
gangliosides. Glucosylceramide or GlcCer, Glcβ1-1Cer; lactosylceramide or LacCer, Galβ1-4Glcβ1-1Cer; gangliotriaosylceramide
or GgOse3Cer or Gg3, GalNAcβ1-4Galβ1-4Glcβ1-1Cer; gangliotetraosylceramide or GgOse4Cer or Gg4, Galβ1-3GalNAcβ1-4Galβ1-4Glcβ1-1Cer;
gangliopentaosylceramide or GgOse5Cer, GalNAcβ1-4Galβ1-3GalNAcβ1-4Galβ1-4Glcβ1-1Cer; gangliohexaosylceramide or GgOse6Cer,
Galβ1-3GalNAcβ1-4Galβ1-3GalNAcβ1-4Galβ1-4Glcβ1-1Cer. GM3, II3NeuAc-LacCer; GM1 or GM1a, II3NeuAc-GgOse4Cer; GM1b, IV3NeuAc-GgOse4Cer;
GalNAc-GM1b, IV3NeuAc-GgOse5Cer; GD1a, IV3NeuAc, II3NeuAc-GgOse4Cer; GD1b, II3(NeuAc)2-GgOse4Cer; GD1c, IV3(NeuAc)2-GgOse4Cer;
GD1α, IV3NeuAc, III6NeuAc-GgOse4Cer. Only NeuAc-substituted gangliosides are presented in this list of abbreviations
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
14.
Glycosylation is one of the most important post-translational modifications. It is clear that the single step of β1,4-galactosylation
is performed by a family of β1,4-galactosyltransferases (β1,4-GalTs), and that each member of this family may play a distinct
role in different tissues and cells. β1,4-GalT I and V are involved in the biosynthesis of N-linked oligosaccharides and play
roles in sciatic nerve regeneration after sciatic nerve injury. In the present study, the expression of β1,4-galactosyltransferase
(β1,4-GalT) I, V mRNAs and Galβ1-4GlcNAc group were examined in rat gastrocnemius muscles after sciatic nerve crush and transection.
Real time PCR revealed that β1,4-GalT I and V mRNAs expressed at a high level in normal gastrocnemius muscles and decreased
gradually from 6 h, reached the lowest level at 2 weeks, then restored gradually to relatively normal level at 4 weeks after
sciatic nerve crush. In contrast, in sciatic nerve transection model, β1,4-GalT I and V mRNAs decreased gradually from 6 h,
and remained on a low level at 4 weeks in gastrocnemius muscles after sciatic nerve transection. In situ hybridization indicated that β1,4-GalT I and V mRNAs localized in numerous myocytes and muscle satellite cells under normal
conditions and at 4 weeks after sciatic nerve crush, and in a few muscle satellite cells at 4 weeks after sciatic nerve transection.
Furthermore, lectin blotting showed that the expression level of the Galβ1–4GlcNAc group decreased from 6 h, reached the lowest
level at 2 weeks, and restored to relatively normal level at 4 weeks after sciatic nerve crush. RCA-I lectin histochemistry
demonstrated that Galβ1–4GlcNAc group localized in numerous membranes of myocytes and muscle satellite cells in normal and
at 4 weeks after sciatic nerve crush, and in a few muscle satellite cells at 2 and 4 weeks after sciatic nerve transection.
These results indicated that the expressions of β1,4-GalT I, V mRNAs and Galβ1–4GlcNAc group were involved in the process
of denervation and reinnervation, which suggests that β1,4-GalT I, V mRNAs and Galβ1-4GlcNAc group may play an important role
in the muscle regeneration. 相似文献
15.
Kerstin Lidholt Maria Fjelstad Ulf Lindahl Fumitaka Goto Tomoya Ogawa Hiroshi Kitagawa Kazuyuki Sugahara 《Glycoconjugate journal》1997,14(6):737-742
Two glycosaminoglycan-protein linkage tetrasaccharide-serine compounds, GlcAβ1-3Galβ1-3Galβ1-4Xylβ1-O-Ser and GlcAβ1-3Gal(4-O-sulfate)β1-3Galβ1-4Xylβ1-O-Ser,
were tested as hexosamine acceptors, using UDP-[3H]GlcNAc and UDP-[3H]GalNAc as sugar donors, and solubilized mouse mastocytoma
microsomes as enzyme source. The nonsulfated Ser-tetrasaccharide was found to function as an acceptor for a GalNAc residue,
whereas the Ser-tetrasaccharide containing a sulfated galactose unit was inactive. Characterization of the radio-labelled
product by digestion with α-N-acetylgalactosaminidase and β-N-acetylhexosaminidase revealed that the [3H]GalNAc unit was α-linked,
as in the product previously synthesized using serum enzymes, and not β-linked as found in the chondroitin sulfate polymer.
Heparan sulfate/heparin biosynthesis could not be primed by either of the two linkage Ser-tetrasaccharides, since no transfer
of [3H]GlcNAc from UDP-[3H]GlcNAc could be detected. By contrast, transfer of a [3H]GlcNAc unit to a [GlcAβ1-4GlcNAcα1-4]2-GlcAβ1-4-aMan
hexasaccharide acceptor used to assay the GlcNAc transferase involved in chain elongation, was readily detected. These results
are in agreement with the recent proposal that two different N-acetylglucosaminyl transferases catalyse the biosynthesis of
heparan sulfate. Although the mastocytoma system contains both the heparan sulfate/heparin and chondroitin sulfate biosynthetic
enzymes the Ser-tetrasaccharides do not seem to fulfil the requirements to serve as acceptors for the first HexNAc transfer
reactions involved in the formation of these polysaccharides.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
16.
Novel oligosaccharide has suppressive activity against human leukemia cell proliferation 总被引:1,自引:0,他引:1
Hosomi O Misawa Y Takeya A Matahira Y Sugahara K Kubohara Y Yamakura F Kudo S 《Glycoconjugate journal》2009,26(2):189-198
Various oligosaccharides containing galactose(s) and one glucosamine (or N-acetylglucosamine) residues with β1–4, α1–6 and β1–6 glycosidic bond were synthesized; Galβ1–4GlcNH2, Galα1–6GlcNH2, Galα1–6GlcNAc, Galβ1–6GlcNH2, Galβ1–4Galβ1–4GlcNH2 and Galβ1–4Galβ1–4GlcNAc. Galα1–6GlcNH2 (MelNH2) and glucosamine (GlcNH2) had a suppressive effect on the proliferation of K562 cells, but none of the other saccharides tested containing GlcNAc
showed this effect. On the other hand, the proliferation of the human normal umbilical cord fibroblast was suppressed by none
of the saccharides other than GlcNH2. Adding Galα1–6GlcNH2 or glucosamine to the culture of K562 cell, the cell number decreased strikingly after 72 h. Staining the remaining cells
with Cellstain Hoechst 33258, chromatin aggregation was found in many cells, indicating the occurrence of cell death. Furthermore,
all of the cells were stained with Galα1–6GlcNH-FITC (MelNH-FITC). Neither the control cells nor the cells incubated with
glucosamine were stained. On the other hand, when GlcNH-FITC was also added to cell cultures, some of them incubated with
Galα1–6GlcNH2 were stained. The difference in the stainability of the K562 cells by Galα1–6GlcNH-FITC and GlcNH-FITC suggests that the
intake of Galα1–6GlcNH2 and the cell death induced by this saccharide is not same as those of glucosamine. The isolation of the Galα1–6GlcNH2 binding protein was performed by affinity chromatography (melibiose-agarose) and LC-MS/MS, and we identified the human heterogeneous
ribonucleoprotein (hnRNP) A1 (34.3 kDa) isoform protein (30.8 kDa). The hnRNP A1 protein was also detected from the eluate(s)
of the MelNH-agarose column by the immunological method (anti-hnRNP-A1 and HRP-labeled anti-mouse IgG (γ) antibodies). 相似文献
17.
Abstract: Myelin-associated glycoprotein (MAG) and Schwann cell myelin protein (SMP) are highly glycosylated members of a newly defined family of cell adhesion molecules belonging to the immunoglobulin superfamily that recognize terminal sialic acid residues on N- and O-linked oligosaccharides. The importance of the N-linked oligosaccharides on MAG were determined by removal of the eight predicted carbohydrate addition sites by site-directed mutagenesis. The results suggest that all eight N-linked glycosylation sites are utilized in COS cells. N-linked glycosylation does not appear to be required for sialic acid-dependent MAG binding to erythrocytes. However, N-linked glycosylation of MAG does play a role in the proper folding of MAG. It was also shown that sialylation in the host cell expressing MAG and SMP could inhibit binding to erythrocytes. The degree to which SMP and MAG erythrocyte binding was affected by sialylation in the host cell was dependent on (a) the level at which MAG was expressed on the surface on the host cell and (b) the presence of MAG ligands on the host cell. The data suggest that cis -ligands on the host cell compete with trans -ligands on the target cell for the binding site(s) on MAG. 相似文献
18.
Perspectives on the significance of altered glycosylation of glycoproteins in cancer 总被引:13,自引:0,他引:13
No abstract Abbreviations: Sia, sialic acid, type unspecified; Tn antigen, GalNAcα 1-O-Ser/Thr; T antigen, Galβ1-3GalNAcα-O-Ser/Thr;
Sialyl LewisX, Siaα2-3Galβ1-4(Fucα1-3)GlcNAc; Sialyl Lewisa, Siaα2-3Galβ1-3(Fucα1-4)GlcNAc; Sialyl-Tn antigen, Siaα2-6GalNAcα1-O-Ser/Thr;
FucT, fucosyltransferase; ST, sialyltransferase.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
19.
Laidler P Lityńska A Hoja-Łukowicz D Łabedz M Przybyło M Ciołczyk-Wierzbicka D Pocheć E Trebacz E Kremser E 《Cancer immunology, immunotherapy : CII》2006,55(1):112-118
The repertoire of oligosaccharide components of cellular glycoproteins significantly contributes to cell adhesion and communication.
In tumor cells, alteration in cellular glycosylation may play a key role in giving rise to invasive and metastatic potential.
Over 100 melanoma cell lines deposited in the ESTDAB Melanoma Cell Bank (Tubingen, Germany) were studied for the characteristic
glycan composition related to tumor progression. Analysis of: (1) cell adhesion to extracellular matrix proteins—fibronectin,
laminin, and collagen; (2) the expression of selected glycosyltransferases—α2,3(Galβ1,3)- and α2,3(Galβ1,4)-sialyltransferases,
α1,2- and α1,3-fucosyltransferases, and N-acetylglucosaminyltransferase V; (3) characterization of N-glycans was carried out
on uveal (4), primary cutaneous (6), and metastatic (96) melanoma cell lines. Results showed that uveal cells did not adhere
to any of the substrates and, in general, possessed less glycans containing α-2,6- and α-2,3-linked sialic acid. The average
number of polypeptides bearing β-1,6-branched tri- and tetra antennary glycans(characteristic of the metastatic phenotype)were
similar in uveal, primary cutaneous, and metastatic melanoma cell lines. Characterization of N-glycans may open a new perspective
in the search for specific glycoproteins that could become targets for the therapeutic modulation of melanoma.
This article is a symposium paper from the conference “Progress in Vaccination against Cancer 2004 (PIVAC 4)”, held in Freudenstadt-Lauterbad,
Black Forest, Germany, on 22–25 September 2004 相似文献
20.
North SJ Koles K Hembd C Morris HR Dell A Panin VM Haslam SM 《Glycoconjugate journal》2006,23(5-6):345-354
With the complete genome sequence of Drosophila melanogaster defined a systematic approach towards understanding the function of glycosylation has become possible. Structural assignment
of the entire Drosophila glycome during specific developmental stages could provide information that would shed further light on the specific roles
of different glycans during development and pinpoint the activity of certain glycosyltransferases and other glycan biosynthetic
genes that otherwise might be missed through genetic analyses. In this paper the major glycoprotein N- and O-glycans of Drosophila embryos are described as part of our initial undertaking to characterize the glycome of Drosophila melanogaster. The N-glycans are dominated by high mannose and paucimannose structures. Minor amounts of mono-, bi- and tri-antennary complex
glycans were observed with GlcNAc and Galβ1–4GlcNAc non-reducing end termini. O-glycans were restricted to the mucin-type
core 1 Galβ1-3GalNAc sequence. 相似文献