Regional and cellular localization of glycosyltransferases in rat small intestine Changes in enzymes with differentiation of intestinal epithelial cells

Kim, Young S.; Perdomo, Jose; Ochoa, Pamela; Isaacs, Richard

doi:10.1016/0005-2744(75)90150-3

Cited by 40 publications

(11 citation statements)

References 26 publications

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“…Addition of different sugars to the surface glycoconjugates during maturation of the cell may account for these changes (Zieske & Bernstein, 1982). This view is consistent with the fact that glycosyl transferase activity is linked to the differentiation of rat gut epithelium (Kim et al, 1975). De Luca has proposed that vitamin A acts as a carrier of glycosyl moieties in the synthesis of glycoconjugates (De Luca, 1977).…”

supporting

confidence: 60%

Effect of retinoic acid and low calcium conditions on surface glycoconjugates defined by differential lectin labelling in mouse epidermal cell culture

1984

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The appearance of cell surface glycoconjugates (detected by fluorescein-isothiocyanate-conjugated lectins and bullous pemphigoid antibody) was serially examined in mouse epidermal cell cultures treated with trans-retinoic acid and aromatic retinoic acid (etretinate) and in cultures maintained under low calcium conditions. The changes in lectin staining occurred in concert with the process of differentiation as assessed by cell morphology and colony growth characteristics, and they correlated with the patterns observed in whole mouse skin. The keratocyte cultures treated with retinoic acid showed delayed and reduced differentiation and stratification, and this was associated with markedly reduced binding of lectins specific for N-acetyl-glucosamine and fucose. The low calcium concentration produced similar changes. Thus, the loss of surface glycoconjugates in the epidermal cell culture system was not specific for either retinoic acid or low calcium, but correlated with the degree of cell differentiation.

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confidence: 60%

Effect of retinoic acid and low calcium conditions on surface glycoconjugates defined by differential lectin labelling in mouse epidermal cell culture

1984

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“…y-Glutamyl cyclotransferase and the enzymes required for glutathione synthesis are not specifically localized to either the crypt or villus tip cells but are present in both. The crypt cells have a high concentration of glutathione (4-5 mM) (8)(9)(10)(11)(12)(13)(14)(15)(16). Three classes of intestinal enzymes have been found: (a) Activities that are much higher in the crypt cells as compared to the villus cells, e.g., thymidine kinase, aspartate transcarbamylase, and uridine kinase.…”

mentioning

confidence: 99%

Glutathione and gamma-glutamyl cycle enzymes in crypt and villus tip cells of rat jejunal mucosa.

Cornell¹,

Meister²

1976

Proc. Natl. Acad. Sci. U.S.A.

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Villus tip cells and crypt cells of rat jejunal mucosa were separated bythe planing procedure of Imondi et a]. and were studied with respect to their activities of the enzymes of the 'y-glutamyl cycle and glutathione content.The villus tip cells exhibit much higher y-glutamyl transpeptidase activities than do the crypt cells; thus, y-glutamyl transpeptidase appears to be a villus-specific enzyme. y-Glutamyl cyclotransferase and the enzymes required for glutathione synthesis are not specifically localized to In the present work, the micrometer planing technique devised by Imondi et al. (7) was used to separate the epithelial cells of rat jejunum. The intracellular concentration of glutathione and the activities of enzymes involved in glutathione metabolism were examined; two of these ('y-glutamyl cysteine synthetase, glutathione synthetase) catalyze the synthesis of glutathione from its constituent amino acids, and two (y-glutamyl transpeptidase, y-glutamyl cyclotransferase) are involved in the major degradative pathway of glutathione metabolism (17). The uptake of amino acids by the isolated crypt and villus cells was also studied. Methods. Male Sprague-Dawley rats (250-300 g) were housed in stainless steel cages with wire mesh bottoms; the animals were fed ad lib. on standard laboratory rat chow. Groups of rats were fasted for 24 or 48 hr; some were fasted for 24 hr, and then fed ad lib. with cane sugar cubes. Other rats were fasted for 24 hours then fed ad lib. a protein mixture prepared by mixing 8.0 g of gelatin (Knox) and 10 g of casamino acids (Difco) with 400 ml of water.The animals were sacrificed by decapitation and their small intestines were excised. The duodenum was removed and the first 18 cm of the jejunum was cut into three sections, each of which was mounted on the tissue planing device and planed at 125 ,um depths according to the method of Imondi et al. (7). The fractions were quick-frozen in petri dishes placed on dry ice. Five fractions were obtained from the animals fed ad lib. For the enzyme studies the cells were thawed and homogenized in five volumes (weight/volume) of 10 mM MgCl2, 10 mM Tris-HCl (pH 7.6). The homogenate was layered on 18% sucrose containing 10 mM MgCl2 and 10 mM Tris-HCl (pH 7.6) and centrifuged at 100,000 X g to sediment y-glutamyl transpeptidase. y-Glutamyl transpeptidase was assayed after diluting the pellet to an appropriate volume with 0.1 M Tris-HCl (pH 8.0). The other enzymes were assayed in the supernatant collected at the top of the sucrose layer. Protein was determined by the method of Lowry (20) using bovine serum albumin as standard. Thymidine kinase was assayed by the method of Klemperer and Haynes (21) except that thymidine and thymidine 5'-phosphate were separated by ascending paper chromatography in tertiary butanol:methylethylketone:water:formic acid (44:44:11:0.26; vol/vol) (22). -y-Glutamyl transpeptidase was assayed with L-y-glutamyl-p-nitroanilide and glycylglycine 420

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“…Moreover, the extent of the intestinal gly cosylation depends on endogenous factors: age [2], localization throughout the intestinal tract [8], or on exogenous factors (vitamin A deficiency [3,9], administration of salycilate drugs [ 13] or phenylbutazone [ 14] or adrener gic agents [4]). With regard to nutrition and especially to food-gastrointestinal tract inter relations, it is essential to find out whether the variations of glycosylation can depend on nutritional factors.…”

Section: Introductionmentioning

confidence: 99%

Biosynthesis of Glycoproteins in the Intestinal Mucosa

Biol¹,

Martin²,

Oehninger³

et al. 1981

Ann Nutr Metab

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To determine the effect of diets on the biosynthesis of glycoproteins in the intestinal mucosa, male Sprague-Dawley rats were fed, ad libitum, high-carbohydrate, high-fat and high-protein diets. In in vivo methodology, the animals from each dietary group received an intraperitoneal injection of [¹⁴C]-fucose, or [¹⁴C]-galactose or [¹⁴C]-glucosamine. Incorporated radioactivity was detected in the different subcellular fractions. In in vitro methodology, five glycosyl-transferases were studied on microsomes and cell sap. In vivo, only the high-fat diet induces a decrease in the incorporation of [¹⁴C]-glucosamine in the macromolecules. In vitro, only the fucosyl-transferase activity is modified by several diets: as compared with an increase in the activity of the control with the age of the animals, high-protein diet induces a slight activation after 2 weeks of diet, while high-carbohydrate and particularly high-fat diets inhibit the enzyme activity. The inhibition is the same when high-fat diet consists of either oil mixture or triolein or oleic acid or linoleic acid and becomes significant with a supplementation rate of 10%.

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Regional and cellular localization of glycosyltransferases in rat small intestine Changes in enzymes with differentiation of intestinal epithelial cells

Cited by 40 publications

References 26 publications

Effect of retinoic acid and low calcium conditions on surface glycoconjugates defined by differential lectin labelling in mouse epidermal cell culture

Effect of retinoic acid and low calcium conditions on surface glycoconjugates defined by differential lectin labelling in mouse epidermal cell culture

Glutathione and gamma-glutamyl cycle enzymes in crypt and villus tip cells of rat jejunal mucosa.

Biosynthesis of Glycoproteins in the Intestinal Mucosa

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