Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P17931 (galectin-3)
 2,860 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Two antigenic polysaccharides were extracted from cell walls of the cross-reactive strains Streptococcus mutans AHT (a) and S. mutans B13 (d). The antigens extracted from walls by the hot formamide method, were purified by affinity chromatography on columns containing the galactose-specific lectin from the castor bean and were found to be diheteroglycans consisting of galactose and glucose. Antigenic specificities of both the serotype-specific and the cross-reactive sites on each polymer were studied: the AHT (a) antigen is determined by D-galactose linked 1 leads to 6 to adjacent sugar, the B13 (d) antigen is determined by D-glucose similarly linked to o its neighbor, and the cross-reactive (a--d) site present on both polymers consists of D-galactose linked 1 leads to 6 to a subterminal sugar moiety. Methylation analysis revealed structural similarities between the purified polysaccharides that may reflect the nature of the cross-reactive sites and differences that may reflect the natures of the specific haptenic regions. Based on these studies, a partial hypothetical structural model is proposed.
 ...
PMID:Chemical, immunochemical, and structural studies of the cross-reactive antigens of Streptococcus mutans AHT and B13. 8 15

Kluyveromyces bulgaricus is a yeast which, upon culture in a calcium-enriched glucose-peptone medium, flocculates. Its flocculation can be reversed by the addition of galactose. In this paper, it is shown that two lectins can be isolated either from the concentrated culture broth or from the supernatant of deflocculated cells suspended in galactose solution. The N-acetylglucosamine-specific lectin, at pH 7.4, agglutinates untreated sheep red blood cells, but agglutinates neither untreated rabbit red blood cells nor glutaraldehyde-fixed sheep or rabbit red blood cells. Conversely, at pH 4.5, this lectin agglutinates glutaraldehyde-fixed sheep red blood cells. The galactose-specific lectin, at pH 7.4, agglutinates both untreated and glutaraldehyde-fixed rabbit red blood cells but does not agglutinate untreated or glutaraldehyde-fixed sheep red blood cells. At pH 4.5, this lectin agglutinates both glutaraldehyde-fixed sheep and rabbit red blood cells and induces flocculation of deflocculated K. bulgaricus cells. In all cases, the agglutination and the flocculation induced by one of these two lectins were inhibited by free or conjugated N-acetyl-D-glucosamine or by free or conjugated D-galactose, respectively. No glycosylhydrolase activity could be detected in the purified lectins.
 ...
PMID:Kluyveromyces bulgaricus yeast lectins. Isolation of N-acetylglucosamine and galactose-specific lectins: their relation with flocculation. 312 81

Agglutination and competition studies suggest that human erythrocyte Band 3 can interact with both mannose/glucose- and galactose-specific lectins. Purified Band 3 reconstituted into lipid vesicles binds concanavalin A, but the nonspecific binding component, measured in the presence of alpha-methylmannoside, is very high. This glycoprotein also carries binding sites for the galactose-specific lectin Ricinus communis agglutinin. Binding was inhibited poorly by lactose, but much more effectively by desialylated fetuin glycopeptides, suggesting that the lectin recognizes a complex oligosaccharide sequence on Band 3. The glycoprotein bears two separate classes of binding sites for R. communis agglutinin. High-affinity binding sites exist which show strong positive cooperativity and correspond in number to the outward-facing Band 3 molecules. A low-affinity binding mode is abolished by 40% ethyleneglycol, suggesting the involvement of hydrophobic lectin-glycoprotein interactions. Studies on binding of R. communis agglutinin to human erythrocytes indicate positively cooperative binding to 7 X 10(5) very-high-affinity sites per cell, and lectin binding is completely inhibitable by lactose. Based on its binding characteristics in vesicles, it seems likely that Band 3 forms the major receptor for this lectin in human erythrocytes. Properties such as positive cooperativity thus appear to be a common feature of the interaction of Band 3 with a variety of lectins of different specificity, both in erythrocytes and lipid bilayers.
 ...
PMID:Interaction of human erythrocyte Band 3 with Ricinus communis agglutinin and other lectins. 397 96

We studied the in vitro ability of lectin-treated murine peritoneal macrophages to attach and phagocytize particulate antigens. Glucose and mannose specific lectins such as Con-A and lentil lectin, as well as complex lactosamine residues specific lectins, such as Phaseolus vulgaris var. cacahuate and Phaseolus coccineus var. alubia, increased the macrophage phagocytic activity towards heterologous erythrocytes, whereas peanut agglutinin, a galactose-specific lectin, diminished the macrophage phagocytic activity. These results suggest that a galactose-N-acetyl-D galactosamine-containing structure could participate as negative modulator of the phagocytic activity.
 ...
PMID:Effect of lectins on mouse peritoneal macrophage phagocytic activity. 785 61

We have previously reported that two carbohydrate-binding proteins (CBP35 and CBP70) can, under appropriate conditions of affinity chromatography, be isolated from HL60 cell nuclear extracts as a complex. Moreover, we have demonstrated that, during affinity chromatography, the CBP70-CBP35 association can be modified by the binding of lactose to CBP35. To determine whether the CBP70-CBP35 association could be disrupted in the nucleus upon lactose binding to CBP35, the behaviors of CBP70 and CBP35 were analyzed in membrane-depleted nuclei of HL60 cells, incubated with or without lactose. This study was performed by using an antiserum that cross-reacts with CBP35 and CBP70, an antiserum that was specifically raised against CBP70, and a monoclonal antibody (Mac 2) reactive against CBP35. Taken together, the results of indirect immunofluorescent staining, immunoblotting experiments, and quantitative flow-cytofluorometric analysis show that (i) CBP70 and CBP35 are present and colocalized in the nuclei incubated without lactose, (ii) all the CBP70 molecules left the nuclei incubated in the presence of lactose, while CBP35 molecules, probably bound to RNA, remained inside the nuclei, and (iii) glucose failed to have the same effect as lactose. These results strongly suggest that, in membrane-depleted nuclei, CBP35 and CBP70 interactions can be altered by a conformational change of CBP35 induced by the binding of lactose to its carbohydrate-recognition domain.
 ...
PMID:Evidence that lactose binding to CBP35 disrupts its interaction with CBP70 in isolated HL60 cell nuclei. 802 May 91

Three carbohydrate-binding proteins with relative molecular masses of 35, 67, and 70 kDa (CBP35, CBP67, and CBP70) have been described to be present in nuclei of mammalian cells, where they are associated with nuclear ribonucleoprotein (RNP) complexes. CBP35 consists of two domains, an N-terminal domain that is homologous to certain regions of proteins of the heterogeneous nuclear RNP complex, and a C-terminal domain that is homologous to beta-galactoside-specific lectins. CBP35 has been proposed, like the glucose-specific lectin, CBP67, to guide RNP complexes through the nuclear pore. Here, we show that exposition of mature rats (6-8 months old) to stress results in binding of nuclear CBP35 to CBP67 which is retained on a column containing immobilized glucose. In contrast to mature animals, nuclear extracts from the livers of old rats (22-24 months old) displayed no detectable stress response.
 ...
PMID:[CBP35-CBP67 interaction in stress response and aging]. 809 39

Previous studies have demonstrated the existence of nuclear carbohydrate binding proteins in a variety of mammalian cells with molecular masses of 35,000, 67,000, and 70,000 (CBP35, CBP67, and CBP70), which are associated with nuclear ribonucleoprotein (RNP) complexes. CBP35 consists of two domains, an amino-terminal portion that is homologous to certain regions of proteins of the heterogeneous nuclear RNP complex, and a carboxyl-terminal portion homologous to beta-galactoside-specific lectins. CBP35 it has been proposed, like the glucose-specific lectin, CBP67, to guide RNP complexes through the nuclear pore. Here we show that the exposure of mature rats to stress induces an increase in nuclear CBP35 bound to CBP67 and retained on immobilized glucose. Nuclear extracts from the livers of old rats displayed no detectable stress response. This CBP35.CBP67 association detected in rat liver is considered with respect to the CBP35.CBP70 association recently observed in HL60 cell nuclear extracts.
 ...
PMID:HnRNP CBP35.CBP67 interaction during stress response and ageing. 824 36

Nuclear proteins were extracted in 2 M NaCl from membrane-depleted nuclei isolated from HL60 cells. Extracted proteins were submitted to affinity chromatography columns containing immobilized glucose, galactose or lactose. The polypeptides present in the different eluted fractions were resolved by SDS-PAGE and were either silver stained or analysed by immunoblotting with monoclonal or polyclonal antibodies, respectively, raised against the glucose-binding protein CBP67 and the galactose-binding proteins CBP35 and L14. The results presented here show that HL60 cell nuclei contain CBP35 and a glucose-binding lectin of 70 kDa (CBP70). These data account for the previously reported binding of neoglycoproteins containing glucosyl and galactosyl residues to HL60 cell nuclei. Furthermore, the present study provides the new information that CBP35 can associate with CBP70 by interactions dependent on the binding of CBP35 to lactose, and the results of some affinity chromatography experiments strongly suggest that CBP35 and CBP70 associate by protein-protein interactions. The potential function of this lactose-mediated interaction is discussed with respect to data recently reported by others showing that CBP35 is involved in in vitro mRNA splicing and that lactose inhibits the processing of the pre-RNA substrate.
 ...
PMID:Evidence for a lactose-mediated association between two nuclear carbohydrate-binding proteins. 844 82

Nonenzymatic glycation has been implicated in the pathogenesis of the dysregulated tissue remodeling that characterizes diabetic glomerulopathy, via the formation of advanced glycation end products (AGEs) and their binding to cell surface receptors. Several AGE-binding proteins have been identified so far, including p60, p90, and the adhesive and growth-regulating lectin galectin-3 (Gal-3), the components of the so-called AGE-receptor complex. This study aimed to evaluate the mesangial expression of the AGE-receptor complex and its modulation by the diabetic milieu, both in vivo, in non-diabetic versus streptozotocin-induced diabetic rats, and in vitro, in mesangial cells exposed to either normal glucose (NG) levels (5.5 mmol/l), as compared with high glucose (HG) levels (30 mmol/l) and iso-osmolar mannitol (M), or to native bovine serum albumin (BSA), as compared with glycated BSA with AGE formation (BSA-AGE) and glycated BSA in which AGE formation was prevented by aminoguanidine (BSA-AM). In vivo, Gal-3 protein and mRNA were not detectable in glomeruli from nondiabetic rats until 12 months after initiating the study. On the contrary, in diabetic rats, Gal-3 expression was observed at 2 months of disease duration, and it increased thereafter. Both p60 and p90 immunoreactivities were observed at the glomerular level with slightly increased expression of p90, but not p60, in diabetic versus nondiabetic animals. In vitro, Gal-3 was not detectable in mesangial cells cultured in NG (although it became evident after a certain number of passages in culture), whereas Gal-3 was detectable in cells grown on BSA. Prolonged exposure (2-4 weeks) of mesangial cells to HG but not to M, as well as growing cells on BSA-AGE and, to a lesser extent, BSA-AM, induced or significantly increased the expression of Gal-3, both protein (up to 2.65-fold) and mRNA (up to 3.10-fold) and its secretion in the medium (by approximately 50%). Both p60 and p90 were demonstrated in mesangial cells under NG conditions, and the expression of p90, but not p60, was upregulated by approximately 20% by HG or BSA-AGE. These results indicate that 1) under basal conditions, Gal-3, unlike p90 and p60, is not detectable in the mesangium but becomes expressed with aging and 2) the diabetic milieu induces or upregulates Gal-3 production, whereas it increases only slightly the expression of p90, but not p60. Gal-3 expression or overexpression may modulate the AGE-receptor-mediated events by modifying the function of the AGE-receptor complex. Additionally, it may exert direct effects on tissue remodeling by virtue of its adhesive and growth-regulating properties.
 ...
PMID:The diabetic milieu modulates the advanced glycation end product-receptor complex in the mesangium by inducing or upregulating galectin-3 expression. 1090 85

Ustilago maydis is an edible parasitic basidiomycete, which specifically infects corn (Zea mays) and teocintle (Z. diploperennis). To characterise the interaction between the basidiomycete and its host organism, we tested the effect of plant lectins with well-known sugar specificity on the growth and germination of U. maydis spores. Lectins specific for N-acetyl-D-galactosamine, such as those from Dolichos biflorus and Phaseolus lunatus, and the wheatgerm agglutinin specific for N-acetyl-D-glucosamine inhibited spore germination, but were ineffective in modifying U. maydis cell growth. The galactose-specific lectin from the corn coleoptyle inhibited both germination and cell growth, while the lectin concanavalin A (mannose/glucose specific) activated spore germination and growth. Our results suggest that specific saccharide-containing receptors participate in regulating the growth and maturation of U. maydis spores.
 ...
PMID:Effect of plant lectins on Ustilago maydis in vitro. 1121 24


1 2 3 4 5 6 Next >>