Context and dating of Aurignacian vulvar representations from Abri Castanet, France.

We report here on the 2007 discovery, in perfect archaeological context, of part of the engraved and ocre-stained undersurface of the collapsed rockshelter ceiling from Abri Castanet, Dordogne, France. The decorated surface of the 1.5-t roof-collapse block was in direct contact with the exposed archaeological surface onto which it fell.

Expression and characterization of a lactosaminoglycan-carrying glycoprotein of Zajdela hepatoma cell surface--structural analysis of the carbohydrate moiety.

In poorly differentiated hepatoma cells, a glycoprotein carrying lactosaminoglycans is identified, and the structure of its glycan moiety is proposed. After membrane solubilization, protein fractionation by gel filtration, and electroelution, this glycoprotein (GPIII) was identified by its affinity for Datura stramonium lectin and its content in large glycopeptides. As shown by PAGE, GPIII has an apparent molecular mass of 100 kDa and is highly glycosylated (36%).

Structural differences between complex-type Asn-linked glycan chains of glycoproteins in rat hepatocytes and Zajdela hepatoma cells.

Using serial lectin-affinity chromatography, glycosidase digestion, and NMR and methylation analysis, the structures of complex N-linked glycan chains (M(r) range 2000-3500) of rat hepatocytes and poorly differentiated chemically transformed Zajdela ascites hepatoma cells were determined and compared. The results revealed considerable differences between the two cell types: (i) hepatoma cells only expressed tri- and/or tetra-antennary complex N-linked glycan chains, whereas hepatocytes displayed large amounts of bi-antennary N-linked structures and smaller amounts of tri-/tetra-antennary structures; (ii) 20% of the glycan chains in hepatoma cells contained a bisecting GlcNAc residue which was beta (1,4)-linked to the beta-mannosyl residue of the core and was not detected in the hepatocytes; (iii) hepatoma cells expressed a high proportion of the fucosylated or not GlNAc beta (1,6) Man alpha 1-->branch, whereas hepatocytes only contained a little of this branch; (iv) hepatoma cells, but not hepatocytes, exhibited a repeating (Gal beta(1,4) GlcNAc beta (1,3)) sequence characteristic of poly-N-acetyllactosaminoglycans. These glycans were capped by both alpha-galactosyl and sialyl residues; (v) The alpha (2,3)/alpha (2,6)-linkage ratio of sialic acid was significantly higher in hepatoma cells (4/1 vs.

Identification of peanut agglutinin receptors related to the state of tumoral liver cell differentiation.

The relationship between cell differentiation/tumorisation and plasma membrane glycoproteins was approached using peanut agglutinin (PNA) a lectin specific for the Gal-beta(1,3)GalNAc sequence and a homologous cell system consisted of normal rat hepatocytes (HyC) and a poorly differentiated hepatoma (ZHC). This work is focused on the molecular nature of PNA receptors. PNA bound strongly to ZHC, but bound very weakly, if at all to hepatocytes.

Immunological screening of a glycoprotein antigen expressed by Zajdela ascites hepatoma cells on normal rat tissues and tumour cells.

Expression of the glycoprotein MII2 antigen originally identified in Zajdela ascites hepatoma cells was investigated in several normal rat tissues and in more or less differentiated tumours using biochemical and immunological approaches. SDS-polyacrylamide gel electrophoresis followed by fluorography or immunoblotting with an antiserum raised against the purified MII2 antigen revealed that this antigen was absent from normal liver cells. ELISA assays, indirect immunofluorescence and immunoprecipitation experiments using the same antiserum showed that this glycoprotein was not expressed in various normal tissues such as liver, spleen, lung, pancreas, intestine and stomach, but it was unexpectedly detected in kidney and thymic tissues.

Biosynthesis of high molecular weight polylactosamine-type glycopeptides in rat Zajdela hepatoma ascites cells.

The first steps of the biosynthetic pathway of high molecular weight polylactosamine-type glycopeptides from rat Zajdela hepatoma cells were studied by pulse-chase experiments, biochemical analysis and by inhibition of N-glycosylation. It is clear that this process involves firstly the transfer of a lipid-linked high-mannose oligosaccharide precursor to a protein moiety in a similar way to that of N-linked glycopeptides of a more common size range according to the classical 'cycle of dolichol'. In the presence of enzymes which are inhibitors of the processing of high-mannose oligosaccharide chains, this class of oligosaccharides was considerably increased, whereas polylactosamine chains and lower complex N-linked glycopeptides were concomitantly decreased in the same kinetics and the same ratio.

Isolation, molecular and biological properties of a lectin from rice embryo: relationship with wheat germ agglutinin properties.

Rice lectin (Oryza sativa, var. Balilla 28) was purified from defatted embryos by aqueous acid extraction at pH 1.3 followed by ammonium sulfate precipitation between 2 and 4 M, affinity chromatography on agarose-p-aminophenyl-beta-D-N-acetylglucosamine, and gel filtration on AcA 54.

Changes in surface glycopeptides after malignant transformation of rat liver cells and during the regression of hepatoma cells.

Normal liver cells, Zajdela's hepatoma cells, and regressing hepatoma cells were metabolically labeled with either radioactive glucosamine or mannose. Glycopeptides obtained by exhaustive pronase digestion of these cells were compared after fractionation by gel filtration on Bio-Gel P-6. Chemical analysis, affinity chromatography on immobilized lectins, alkaline treatment, and susceptibility toward endo-beta-N-acetylglucosaminidase and tunicamycin revealed dramatic changes in the glycopeptide patterns of transformed cells during the recovery of normal phenotype.

Calmodulin in lymphocyte mitogenic stimulation and in lymphoid cell line growth.

Calmodulin levels are elevated three- to fourfold in the dividing cells, resulting from the lectin-induced stimulation of fresh human lymphocytes. This increase in calmodulin appears to be related mainly to progression into S phase and supports the hypothesis that calmodulin might be crucial in regulating the progression of lymphoblasts through their division cycle. Calmodulin levels are higher in a lymphoid cell line derived from human acute lymphoblastic leukemia blood cells than in a lymphoid cell line derived from normal human blood cells, suggesting that calmodulin could be an important mediator of the leukemogenetic process.

Structure and stability of Ricinus communis haemagglutinin.

The molecular properties of the haemagglutinin of Ricinus communis (RCA I or RCA 120) were evaluated by analytical ultracentrifugation, light-scattering, c.d. and fluorescence.

The structure of the O-glycosidic oligosaccharide chains of the major Zajdela hepatoma ascites-cell-membrane glycoprotein.

Glycoprotein MII2, the major cell surface glycoprotein (molecular mass 110 kDa) of Zajdela hepatoma ascites cells, contains about 25 O-glycosidic oligosaccharide chains per molecule. They were released as oligosaccharide-alditols by alkaline borohydride treatment of MII2, and purified by gel filtration on Bio-Gel P-6 followed by high-voltage paper electrophoresis. Four oligosaccharide-alditol fractions (A-D) were obtained in relative yields of 8:6:3:3.

Biochemical analysis of bovine testicular anti-Müllerian hormone.

Direct biochemical analysis has been applied to bovine testicular anti-Müllerian hormone (AMH), purified from incubation medium of bovine fetal testes by immunochromatography on a monoclonal antibody. The hormone contains a high proportion of hydrophobic amino acids and 13.5% carbohydrate.

In vitro study of the comparative behaviour of a human acute lymphoblastic leukemia cell line and a reference normal cell line towards the effects of a mitogenic lectin.

An in vitro study of the behaviour of a human acute lymphoblastoid leukemia cell line (REH) towards the action of a mitogenic lectin of Robinia pseudoacacia was carried out. The results were compared with those a reference cell line (LHN13) established from normal human lymphocytes. In both cell lines, the lectin induces agglutination (measured by counting the number of aggregates as well as the number of cells in each aggregate) and decrease of growth (measured by counting the number of cells and the incorporation of tritiated thymidine into TCA-precipitable material per 10(6) cells).

Purification of the rice embryo lectin and its binding to nitrogen-fixing bacteria from the rhizosphere of rice.

A lectin was purified from rice embryos by aqueous acid extraction of crude embryo powder, followed by ammonium sulfate precipitation, affinity chromatography on agarose p-aminophenyl-beta-D-N-acetylglucosamine and gel-filtration on AcA 54. Its homogeneity was checked by polyacrylamide gel electrophoresis, gel-filtration and immunological methods. The hemagglutinating activity of the purified rice lectin was 0.

[Comparative analysis of the glycopeptides in normal liver cells and in Zajdela ascitic hepatoma cells in the rat].

Glycopeptides obtained after pronase digestion of normal rat hepatocytes and Zajdela hepatoma cells after 3H-mannose or 3H-glucosamine incorporation were compared. In both cell types, the glycopeptides were resolved in four peaks after gel filtration on Biogel P6 with a different distribution of radioactivity in normal and tumoral cells. The first peak (I) contained high molecular weight glycopeptides, and particularly a megaloglycopeptide (MW 70,000) exclusively present in malignant cells.

Correlation between changes in cell adhesion and the ratio of N- to O-linked glycopeptides during chick embryo development.

After treatment with trypsin, chick embryo fibroblasts exhibited an age-related difference in their capacity to readhere to the substratum, since 8-day-cells readhered more rapidly than 16-day-cells. Treatment with tunicamycin altered embryo cell readhesion to the substratum in varying degrees, depending on the duration of drug treatment and of readhesion assay. The effect of tunicamycin was not toxic and was totally reversible with time after its removal.

Decrease in human lymphocyte surface glycoconjugates in leukemia as demonstrated by lectin binding.

Qualitative variations in the glycoconjugates which make up the lectin receptor sites on the membranes of leukemic lymphocytes, compared with those of normal cells, have been studied by the use of three tritiated lectins: Robinia pseudoacacia lectin, Concanavalin A and Ricinus communis (var. Sanquineus) agglutinin (RCA 120). The binding specificity of these lectins has been demonstrated using specific determinants: alpha-methylmannoside and galactose for Concanavalin A and Ricinus communis agglutinin respectively.

Approach to the mechanism of Zajdela's hepatoma cell growth inhibition induced by concanavalin A and phytohaemagglutinin.

Cell growth of tumour ascites cells was inhibited by concanavalin A, phytohaemagglutinin and Ricinus lectin at 2-100 micrograms/ml. As expected, the Ricinus lectin inhibited the protein synthesis estimated by leucine incorporation and decreased thymidine incorporation, whereas concanavalin A and phytohaemagglutinin stimulate the uptake and the incorporation of both leucine and thymidine, and thus, synthesis of protein and DNA. These results suggest that different mechanisms are involved in the hepatoma cell growth inhibition by the lectins.

Purification and characterization of a major cell surface glycoprotein in Zajdela ascites hepatoma cells which displays a potent concanavalin A receptor activity.

A major cell surface sialoglycoprotein with Concanavalin A receptor activity has been isolated from rat Zajdela ascites hepatoma cells. The sialic acid residues of the plasma membrane glycoproteins were specifically labeled by oxidation and NaIO4 followed by reduction with NaB3H4. Surface-labeled glycoproteins were released by short incubations with TPCK-trypsin at 37 degrees C and then separated by gel filtration on Sepharose 6B column.

Cryoinsolubility of peanut agglutinin. Effect of saccharides and neutral salts.

Peanut agglutinin (PNA) has been shown to be insoluble at low temperatures. This cryoinsolubility has been studied by means of absorption spectroscopy, fluorescence, circular dichroism, and analytical ultracentrifugation. It was found to be dependent on pH, temperature, and protein concentration.

Localization and overall structure of a mannose-rich glycopeptide from a pathologic immunoglobulin.

The structure of a mannose-rich glycopeptide from a human pathological IgM has been investigated. It belongs to the group I (simple) glycopeptides and contains only mannose and N-acetylglucosamine residues in a molar ratio of 10:2. The structures of its oligosaccharide moiety and peptide chain have been determined: its molecular localization is specified and the relation between its biosynthesis and the oligosaccharide structure determine is discussed.