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Marion J, Petersen YM, Romé V, Thomas F, Sangild PT, Le Dividich J, Le Huërou-Luron I. Early weaning stimulates intestinal brush border enzyme activities in piglets, mainly at the posttranscriptional level. J Pediatr Gastroenterol Nutr 2005; 41:401-10. [PMID: 16205506 DOI: 10.1097/01.mpg.0000177704.99786.07] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Weaning-associated anorexia is the main factor responsible for structural alterations of the small intestine. However, whether weaning and the postweaning feed intake level affect disaccharidase and peptidase gene expression remains to be elucidated. METHODS Adaptation of the small intestine to early weaning at 7 days of age and the effects of postweaning feed intake were investigated on 56 pigs in two trials. Structural parameters and gene expression and activities of intestinal lactase, maltase, sucrase, aminopeptidases A and N, and dipeptidyl peptidase IV were determined along the small intestine. RESULTS Within 3 days, weaning induced increases in maltase, sucrase, and peptidase specific activities (P < 0.05) and a decrease in lactase activity and villous height (P < 0.05). Only for maltase activity were the weaning-induced changes closely correlated with corresponding mRNA levels. In weaned piglets, aminopeptidase N activity was consistently stimulated and dipeptidyl peptidase IV depressed by high level of feed intake but without effects on the corresponding mRNA levels. Furthermore, the longitudinal distribution of enzyme activities along the small intestine showed poor correlation with the corresponding mRNA levels. CONCLUSION Early weaning in pigs is associated with a remarkable capacity of the small intestine to rapidly increase the activity of key brush border enzymes. This adaptation, largely independent on feed intake for intestinal enzyme mRNAs and disaccharidase activities, occurred at the posttranscriptional rather than at the transcriptional level of enzyme biosynthesis (except for maltase). The length of the postweaning anorexia period did not affect the subsequent intestinal capacity for villous elongation but may postpone maturation of peptidase activities.
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Affiliation(s)
- Julia Marion
- Unité Mixte de Recherche INRA-Agrocampus Livestock Production Systems, Animal and Human Nutrition, St-Gilles, France
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Herbig K, Chiang EP, Lee LR, Hills J, Shane B, Stover PJ. Cytoplasmic serine hydroxymethyltransferase mediates competition between folate-dependent deoxyribonucleotide and S-adenosylmethionine biosyntheses. J Biol Chem 2002; 277:38381-9. [PMID: 12161434 DOI: 10.1074/jbc.m205000200] [Citation(s) in RCA: 198] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Folate-dependent one-carbon metabolism is required for the synthesis of purines and thymidylate and for the remethylation of homocysteine to methionine. Methionine is subsequently adenylated to S-adenosylmethionine (SAM), a cofactor that methylates DNA, RNA, proteins, and many metabolites. Previous experimental and theoretical modeling studies have indicated that folate cofactors are limiting for cytoplasmic folate-dependent reactions and that the synthesis of DNA precursors competes with SAM synthesis. Each of these studies concluded that SAM synthesis has a higher metabolic priority than dTMP synthesis. The influence of cytoplasmic serine hydroxymethyltransferase (cSHMT) on this competition was examined in MCF-7 cells. Increases in cSHMT expression inhibit SAM concentrations by two proposed mechanisms: (1) cSHMT-catalyzed serine synthesis competes with the enzyme methylenetetrahydrofolate reductase for methylenetetrahydrofolate in a glycine-dependent manner, and (2) cSHMT, a high affinity 5-methyltetrahydrofolate-binding protein, sequesters this cofactor and inhibits methionine synthesis in a glycine-independent manner. Stable isotope tracer studies indicate that cSHMT plays an important role in mediating the flux of one-carbon units between dTMP and SAM syntheses. We conclude that cSHMT has three important functions in the cytoplasm: (1) it preferentially supplies one-carbon units for thymidylate biosynthesis, (2) it depletes methylenetetrahydrofolate pools for SAM synthesis by synthesizing serine, and (3) it sequesters 5-methyltetrahydrofolate and inhibits SAM synthesis. These results indicate that cSHMT is a metabolic switch that, when activated, gives dTMP synthesis higher metabolic priority than SAM synthesis.
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Affiliation(s)
- Katherine Herbig
- Cornell University, Division of Nutritional Sciences, Ithaca, New York 14853, USA
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Jiang L, Lawsky H, Coloso RM, Dudley MA, Ferraris RP. Intestinal perfusion induces rapid activation of immediate-early genes in weaning rats. Am J Physiol Regul Integr Comp Physiol 2001; 281:R1274-82. [PMID: 11557636 DOI: 10.1152/ajpregu.2001.281.4.r1274] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
C-fos and c-jun are immediate-early genes (IEGs) that are rapidly expressed after a variety of stimuli. Products of these genes subsequently bind to DNA regulatory elements of target genes to modulate their transcription. In rat small intestine, IEG mRNA expression increases dramatically after refeeding following a 48-h fast. We used an in vivo intestinal perfusion model to test the hypothesis that metabolism of absorbed nutrients stimulates the expression of IEGs. Compared with those of unperfused intestines, IEG mRNA levels increased up to 11 times after intestinal perfusion for 0.3-4 h with Ringer solutions containing high (100 mM) fructose (HF), glucose (HG), or mannitol (HM). Abundance of mRNA returned to preperfusion levels after 8 h. Levels of c-fos and c-jun mRNA and proteins were modest and evenly distributed among enterocytes lining the villi of unperfused intestines. HF and HM perfusion markedly enhanced IEG mRNA expression along the entire villus axis. The perfusion-induced increase in IEG expression was inhibited by actinomycin-D. Luminal perfusion induces transient but dramatic increases in c-fos and c-jun expression in villus enterocytes. Induction does not require metabolizable or absorbable nutrients but may involve de novo gene transcription in cells along the villus.
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Affiliation(s)
- L Jiang
- Graduate School of the Biomedical Sciences, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey 07103-2714, USA
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Stoll B, Burrin DG, Henry JF, Jahoor F, Reeds PJ. Dietary and systemic phenylalanine utilization for mucosal and hepatic constitutive protein synthesis in pigs. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:G49-57. [PMID: 9886978 DOI: 10.1152/ajpgi.1999.276.1.g49] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The objective of this study was to quantify the utilization of dietary and systemic phenylalanine for mucosal and hepatic constitutive protein synthesis in piglets. Seven female piglets (7.6 kg) bearing arterial, portal, peripheral venous, and gastric catheters were fed a high-protein diet and infused intragastrically with U-13C-labeled protein and intravenously with [2H(phenyl)5]phenylalanine ([2H5]phenylalanine) for 6 h. The isotopic enrichment of the two phenylalanine tracers was measured in arterial and portal blood, in mucosal and hepatic-free and protein-bound phenylalanine, and in very low-density apolipoprotein B-100, albumin, and fibrinogen. The relative isotopic enrichments of the tracers in mucosal-free (ratio of 2H5- to U-13C-labeled = 0.20 +/- 0.05) and protein-bound (0.32 +/- 0.08) phenylalanine differed significantly (P < 0.01). Although this suggests preferential use of arterial phenylalanine for mucosal protein synthesis, on a molar basis, 59 +/- 6% of the mucosal protein was derived from dietary phenylalanine. There were significant differences (P < 0.025) between the relative labeling of the two tracers in arterial (ratio of 2H5- to U-13C-labeled = 1.25 +/- 0.48) and portal (ratio of 2H5- to U-13C-labeled = 0.72 +/- 0.18) phenylalanine. The mean ratio of the two tracers in all proteins of hepatic origin that were analyzed (0.69 +/- 0.18) was similar to that of portal phenylalanine. We conclude that in the fed state portal phenylalanine is preferentially used for constitutive as well as secreted hepatic protein synthesis.
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Affiliation(s)
- B Stoll
- United States Department of Agriculture/Agricultural Research Service Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
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Stoll B, Burrin DG, Henry J, Yu H, Jahoor F, Reeds PJ. Dietary amino acids are the preferential source of hepatic protein synthesis in piglets. J Nutr 1998; 128:1517-24. [PMID: 9732313 DOI: 10.1093/jn/128.9.1517] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
To investigate the utilization of dietary amino acids for hepatic protein synthesis, seven female pigs ( 28 d old, 7.5 kg) were implanted with catheters in a carotid artery, the jugular and portal veins, and the stomach. A portal flow probe was also implanted. The pigs were fed a high protein diet once hourly and infused intragastrically with [U-13C]algal protein for 6 h. Amino acid labeling was measured in arterial and portal blood, in the hepatic free and protein-bound pools and in apolipoprotein B-100 (apoB-100), albumin and fibrinogen. The isotopic enrichments of apoB-100-bound [U-13C]threonine, leucine, lysine and phenylalanine were 33, 100, 194 and 230% higher than those of their respective hepatic free amino acid pools (P < 0.01). Using the labeling of apoB-100 to estimate that of the protein synthetic precursor, the fractional rate of hepatic protein synthesis was 42 +/- 2%/d. Between 5 and 8% of the dietary tracer amino acids was used for hepatic protein synthesis. In contrast to the small intestinal mucosa, in which the majority of the metabolized amino acids were apparently catabolized, protein synthesis utilized from 48% (threonine) to 90% (lysine) of the hepatic uptake of tracer amino acids. It appears that hepatic protein synthesis consumes nutritionally significant quantities of dietary essential amino acids in first pass and that extracellular, especially portal, essential amino acids are channeled to hepatic protein synthesis in the fed state.
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Affiliation(s)
- B Stoll
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
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Dudley MA, Burrin DG, Wykes LJ, Toffolo G, Cobelli C, Nichols BL, Rosenberger J, Jahoor F, Reeds PJ. Protein kinetics determined in vivo with a multiple-tracer, single-sample protocol: application to lactase synthesis. THE AMERICAN JOURNAL OF PHYSIOLOGY 1998; 274:G591-8. [PMID: 9530162 DOI: 10.1152/ajpgi.1998.274.3.g591] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Precise analysis of the kinetics of protein/enzyme turnover in vivo has been hampered by the need to obtain multiple tissue samples at different times during the course of a continuous tracer infusion. We hypothesized that the problem could be overcome by using an overlapping (i.e., staggered) infusion of multiple stable amino acid isotopomers, which would take the place of multiple tissue samples. We have measured, in pigs, the in vivo synthesis rates of precursor (rapidly turning over) and mature (slowly turning over) polypeptides of lactase phlorizin hydrolase (LPH), a model for glycoprotein synthesis, by using an overlapping infusion of [2H3]leucine, [13C1]leucine, [13C1]phenylalanine, [2H5]phenylalanine, [13C6]phenylalanine, and [2H8]phenylalanine. Blood samples were collected at timed intervals, and the small intestine was collected at the end of the infusion. The tracer-to-tracee ratios of each isotopomer were measured in the plasma and jejunal free amino acid pools as well as in purified LPH polypeptides. These values were used to estimate kinetic parameters in vivo using a linear steady-state compartmental model. The fractional synthesis rates of the high-mannose, complex glycosylated and mature brush-border LPH polypeptides, so determined, were 3.3 +/- 1.1%/min, 17.4 +/- 11%/min, and 0.089 +/- 0.02%/min, respectively. We conclude that this multiple-tracer, single-sample protocol is a practicable approach to the in vivo measurement of protein fractional synthesis rates when only a single tissue sample can be obtained. This method has broad application and should be particularly useful for studies in humans.
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Affiliation(s)
- M A Dudley
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
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Dudley MA, Wykes LJ, Dudley AW, Burrin DG, Nichols BL, Rosenberger J, Jahoor F, Heird WC, Reeds PJ. Parenteral nutrition selectively decreases protein synthesis in the small intestine. THE AMERICAN JOURNAL OF PHYSIOLOGY 1998; 274:G131-7. [PMID: 9458782 DOI: 10.1152/ajpgi.1998.274.1.g131] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We investigated the effects of an elemental diet fed parenterally or enterally on total mucosal protein and lactase phlorizin hydrolase (LPH) synthesis. Catheters were placed in the stomach, jugular vein, and carotid artery of 12 3-day-old pigs. Half of the animals were given an elemental regimen enterally and the other half parenterally. Six days later, animals were infused intravenously with [2H3]leucine for 6 h and killed, and the midjejunum of each animal was collected for analysis. The weight of the midjejunum was 8 +/- 1.5 and 17 +/- 1.6 g in parenterally fed and enterally fed piglets, respectively. LPH activities (mumol.min-1.g protein-1) were significantly higher in parenterally vs. enterally fed piglets. Total small intestinal LPH activities were lower in parenterally vs. enterally fed animals. The abundance of LPH mRNA relative to elongation factor-1 alpha mRNA was not different between groups. The fractional synthesis rate of total mucosal protein and LPH was significantly lower in parenterally fed animals (67 +/- 7 and 66 +/- 7%/day, respectively) than in enterally fed animals (96 +/- 7 and 90 +/- 6%/day, respectively). The absolute synthesis rate (the amount of protein synthesized per gram of mucosa) of total mucosal protein was significantly lower in parenterally fed than in enterally fed piglets. However, the absolute synthesis rate of LPH was unaffected by the route of nutrient administration. These results suggest that the small intestine partially compensates for the effects of parenteral feeding by maintaining the absolute synthesis rate of LPH at the same levels as in enterally fed animals.
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Affiliation(s)
- M A Dudley
- United States Department of Agriculture/Agricultural Research Service, Department of Pediatrics, Baylor College of Medicine, Houston, USA
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Lien KA, Sauer WC, Fenton M. Mucin output in ileal digesta of pigs fed a protein-free diet. ZEITSCHRIFT FUR ERNAHRUNGSWISSENSCHAFT 1997; 36:182-90. [PMID: 9246734 DOI: 10.1007/bf01611398] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Daily outputs of mucin in ileal digesta were estimated in three barrows fed a protein-free diet while administered either saline (SAI) or a complete amino acid mixture (AAI) intravenously. The water soluble-ethanol precipitable fraction of ileal digesta (crude mucin; CM) was used to estimate the composition of mucin in ileal digesta. This fraction exhibited a carbohydrate composition characteristic of mucin and had a high threonine, serine and proline content (40 mol/100 mol). The proportions of soluble gastric and intestinal mucins, approximately 27 and 73%, respectively, were estimated from the N-acetylglucosamine (GlcNAc)/N-acetylgalactosamine (GalNAc) ratio in CM. The daily outputs of soluble mucin, 2.75 and 3.41 g/day from SAI and AAI pigs (p = 0.13), respectively, were determined from the GalNAc outputs in CM, assuming the above contributions of gastric and intestinal mucins. The estimated soluble mucin outputs accounted for more than 99% of the fucose, galactose, GalNAc and GlcNAc in CM. Total mucin outputs in ileal digesta, 5.32 and 5.65 g/day from SAI and AAI Pigs (p = 0.24), respectively, were determined from the total GalNAc output in digesta, assuming soluble and insoluble mucin had similar compositions. Based on these outputs, mucin represented approximately 30, 7 to 22, 15 and 11% of the endogenous threonine, proline, serine and protein, respectively, in ileal digesta. Approximately 74, 76, 100 and 53% of the fucose, galactose GalNAc and GlcNAc, respectively, in ileal digesta from pigs in this study was attributed to mucin. The results from this study demonstrate the importance of mucin as a source of some endogenous amino acids and carbohydrates.
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Affiliation(s)
- K A Lien
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Canada
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Dudley MA, Wykes L, Dudley AW, Fiorotto M, Burrin DG, Rosenberger J, Jahoor F, Reeds PJ. Lactase phlorizin hydrolase synthesis is decreased in protein-malnourished pigs. J Nutr 1997; 127:687-93. [PMID: 9164987 DOI: 10.1093/jn/127.5.687] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
We have examined the effect of protein malnutrition on brush border (BB) lactase phlorizin hydrolase (LPH) synthesis in young pigs. Two groups of four 3-wk-old pigs were fed diets containing either 19 g soy protein, 63 g carbohydrate and 5 g fat per 100 g diet (a protein-sufficient diet) or 3 g soy protein, 85 g carbohydrate and 5 g fat per 100 g diet (a protein-deficient diet). After 8 wk of consuming the diets, pigs were infused intravenously with 2H3-leucine for 8 h, then killed. The jejunum was collected for measurement of lactase activity, LPH mRNA abundance and the rate of LPH post-translational synthesis. Lactase activities did not differ between groups (mean 8.1 +/- 1.2 micromol x min(-1) x g mucosa(-1)). LPH mRNA abundance relative to elongation factor-1alpha mRNA (the constitutive/reference mRNA) was significantly (P < 0.05) higher in well-nourished pigs (0.36 +/- 0.03%) than in protein-malnourished pigs (0.21 +/- 0.02%). The rate constants of BB LPH post-translational synthesis were also significantly higher in the well-nourished (103 +/- 9% x d(-1)) than in the protein-malnourished pigs (66 +/- 8% x d(-1)). Further, the absolute synthesis rate of BB LPH, a measure of the amount of enzyme synthesized per gram of tissue, was significantly higher in well-nourished than in protein-malnourished pigs (in arbitrary units, 892 +/- 90 vs. 450 +/- 34, respectively). Thus, protein malnutrition affects both LPH mRNA abundance and post-translational processing in young pigs.
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Affiliation(s)
- M A Dudley
- Department of Pediatrics, Baylor College of Medicine and Texas Children's Hospital, Houston 77030, USA
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Dudley MA, Burrin DG, Quaroni A, Rosenberger J, Cook G, Nichols BL, Reeds PJ. Lactase phlorhizin hydrolase turnover in vivo in water-fed and colostrum-fed newborn pigs. Biochem J 1996; 320 ( Pt 3):735-43. [PMID: 9003357 PMCID: PMC1217992 DOI: 10.1042/bj3200735] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We have estimated the synthesis rates in vivo of precursor and brush-border (BB) polypeptides of lactase phlorhizin hydrolase (LPH) in newborn pigs fed with water or colostrum for 24h post partum. At the end of the feeding period, piglets were anaesthetized and infused intravenously for 3h with L-[4-3H]- phenylalanine. Blood and jejunal samples were collected at timed intervals. The precursor and BB forms of LPH were isolated from jejunal mucosa by immunoprecipitation followed by SDS/PAGE, and their specific radioactivity in Phe determined. The kinetics of precursor and BB LPH labelling were analysed by using a linear compartmental model. Immunoisolated LPH protein consisted of five polypeptides [high-mannose LPH precursor (proLPHh), complex glycosylated LPH precursor (proLPHe), intermediate complex glycosylated LPH precursor (proLPH1i) and two forms of BB LPH]. The fractional synthesis rate (Ks) of proLPHh and proLPHc (approx. 5%/min) were the same in the two groups but the absolute synthesis rate (in arbitrary units, min-1) of proLPHh in the colostrum-fed animals was twice that of the water-fed animals. The Ks values of proLPHi polypeptides were significantly different (water-fed, 3.89%/min; colostrum-fed, 1.6%/min), but the absolute synthesis rates did not differ. The Ks of BB LPH was not different between experimental treatment groups (on average 0.037%/min). However, the proportion of newly synthesized proLPHh processed to BB LPH was 48% lower in colostrum-fed than in water-fed animals. We conclude that in neonatal pigs, the ingestion of colostrum stimulates the synthesis of proLPHh but, at least temporarily, disrupts the processing of proLPH polypeptides to the BB enzyme.
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Affiliation(s)
- M A Dudley
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
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Quaroni A, Paul EC, Nichols BL. Intracellular degradation and reduced cell-surface expression of sucrase-isomaltase in heat-shocked Caco-2 cells. Biochem J 1993; 292 ( Pt 3):725-34. [PMID: 8100414 PMCID: PMC1134174 DOI: 10.1042/bj2920725] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
To investigate the role of post-translational events in intestinal cell differentiation we have studied the effects of heat shock on processing and cell surface delivery of sucrase-isomaltase (SI), dipeptidylpeptidase IV (DPPIV) and aminopeptidase N (APN) in Caco-2 cells. In cells cultured at 42.5 degrees C there was a rapid decline in sucrase activity, while DPPIV and APN were unaffected over a 3-day period. Immunofluorescence staining confirmed the selective disappearance of SI from the surface membrane after only 1 day of culture at 42.5 degrees C. Cell-surface biotinylation of cells metabolically labelled with [35S]methionine 4 h after a switch from 37 degrees C to 42.5 degrees C demonstrated that newly synthesized APN and DPPIV were associated with the surface membrane, while SI was almost completely retained intracellularly. Pulse-chase experiments confirmed that, in these cells, DPPIV and APN were normally processed and vectorially delivered to the cell surface; in contrast, conversion between the two conformationally distinct high-mannose precursor forms of SI (hmP1 and hmP2) was markedly inhibited, a significant fraction of newly synthesized enzyme was degraded, probably in the ER, and an immature form of complex-glycosylated SI precursor (cP) was produced and mostly retained intracellularly. Double labelling of Caco-2 cells for SI and cathepsin D excluded an accumulation of SI in the lysosomes, suggesting that this organelle was not involved in the degradation of SI. These results indicate that the ER may play an important role in intestinal cell differentiation by regulating the conformational maturation, degradation and eventual cellular localization of some digestive enzymes.
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Affiliation(s)
- A Quaroni
- Section of Physiology, Cornell University, Ithaca, NY 14853
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Dudley M, Hachey D, Quaroni A, Hutchens T, Nichols B, Rosenberger J, Perkinson J, Cook G, Reeds P. In vivo sucrase-isomaltase and lactase-phlorizin hydrolase turnover in the fed adult rat. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(19)38692-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Reeds PJ, Burrin DG, Davis TA, Fiorotto ML. Postnatal growth of gut and muscle: competitors or collaborators. Proc Nutr Soc 1993; 52:57-67. [PMID: 8493277 DOI: 10.1079/pns19930037] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- P J Reeds
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Houston, Texas 77030
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