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Query: UNIPROT:P06889 (Mol)
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A lambda cDNA library was prepared from polyadenylated RNA isolated from quiescent human diploid FS-4 fibroblasts stimulated with tumor necrosis factor for 3 h. Differential screening was used to isolate cDNA sequences that are stimulated by tumor necrosis factor. Eight distinct tumor necrosis factor-stimulated gene sequences (designated TSG-1, -6, -8, -12, -14, -21, -27, and -37) were partially sequenced and compared with known sequences from GenBank. TSG-1 was identical to the gene for interleukin-8. TSG-8 corresponded to the gene for monocyte chemotactic and activating factor. TSG-21 and -27 were identical to the genes for collagenase and stromelysin, respectively. The other four sequences showed no homologies with known genes. Patterns of induction of mRNAs corresponding to the eight cloned cDNAs by various cytokines, growth factors, and activators of second messenger pathways were analyzed in FS-4 cells.
Mol Cell Biol 1990 May
PMID:Isolation and characterization of eight tumor necrosis factor-induced gene sequences from human fibroblasts. 218 14

Analysis of the transforming growth factor alpha (TGF alpha) cDNA predicts that the mature TGF alpha polypeptide is cleaved from the extracellular domain of its precursor, which is an integral membrane protein. Furthermore, the cleavage sites for the release of this mitogen are compatible with the participation of an elastaselike protease. We have immunohistochemically localized TGF alpha to the vascular smooth muscle cells in the arterioles. To investigate whether polymorphonuclear (PMN) leukocytic elastase, a blood-borne protease, could process the cell surface TGF alpha, NR6 cells were transfected with the rat TGF alpha cDNA. The cDNA encoded the entire open reading frame, and its expression was under the control of the mouse metallothionein I promoter. A cloned transfectant, termed 1B2, synthesized the TGF alpha precursor in a zinc-inducible manner, and the precursor was localized to the cell surface. Western blot (immunoblot) analysis indicated that treatment of the zinc-induced 1B2 cells with either PMN leukocytic or pancreatic elastase resulted in the release of the mature TGF alpha polypeptide. The released TGF alpha was bioactive, as it was capable of both competing with epidermal growth factor for binding to its receptor and stimulating [3H]thymidine incorporation in the mitogenic assay. Formaldehyde fixation of the 1B2 cells eliminated basal release of TGF alpha but allowed normal processing by both PMN leukocytic and pancreatic elastase to occur. However, human cathepsin G, bovine pancreatic alpha 1-chymotrypsin, collagenase, trypsin, subtilisin, and plasmin failed to release any detectable fragments of the TGF alpha precursor from the fixed cells. The location of TGF alpha in the arterioles and ability of PMN leukocytic elastase to process the membrane-bound TGF alpha precursor suggests a novel role for this elastase at the wound site.
Mol Cell Biol 1990 Sep
PMID:Transforming growth factor alpha in arterioles: cell surface processing of its precursor by elastases. 220 95

Live Haemonchus contortus developmental stages were radioiodinated and then subjected to a stepwise extraction procedure consisting of a buffer extract (with or without detergent) to solubilize putative surface-associated antigenic macromolecules, followed by a detergent/beta-mercaptoethanol (BME) extract to solubilize putative cuticle collagen proteins. A buffer-extracted iodinated 100-kDa protein was present in the free-living, infective L3(2M) stage. This labeled protein was released during in vitro exsheathment of L3(2M) and was not present in the ecdysed second molt (2M) cuticle. In addition to the 100-kDa protein, exsheathment fluid contained a 70-kDa labeled protein that was not extracted from iodinated L3(2M) with either detergent or BME. The data suggest that these proteins are components of the specialized ring portion of the 2M cuticle that is enzymatically ruptured during ecdysis. The L3(2M) and the exsheathed third-stage larvae (L3) contained 3 labeled, BME-extracted, collagenase-sensitive proteins of 108, 88 and 53 kDa. In contrast, four detergent-extracted, collagenase-insensitive, iodinated proteins (143, 81, 58 and 30 kDa) were present in adult H. contortus. The 143-kDa protein was both glycosylated and immunogenic. All 4 adult cuticle proteins were released from the cuticle surface into culture fluids. Furthermore, a cysteine protease was secreted by adults which apparently hydrolyzed the released 81-, 58- and 30-kDa surface proteins.
Mol Biochem Parasitol
PMID:Biochemical and immunochemical characterization of 125I-labeled cuticle components of Haemonchus contortus. 227 98

The effects of recombinant human interleukin-1 alpha (IL-1) on procollagen gene expression were examined in the clonal mouse osteoblastic cell line MC3T3-E1. Cells were grown in Dulbecco's Modified Eagle's Medium containing 10% fetal calf serum and 50 micrograms/ml ascorbic acid. Collagen synthesis was assessed as [3H]proline incorporation into collagenase-digestible protein (CDP). Procollagen mRNA levels were determined by Northern blot analysis using a 32P-labeled alpha 1(I) cDNA. Transcription rates were determined by nuclear run-off assay. IL-1 at 1-1000 pg/ml caused a concentration-dependent inhibition of CDP, which was maximally reduced by 75-80%, and a parallel reduction of procollagen alpha 1(I) mRNA levels. The effects of IL-1 were mimicked by the tumor promoter phorbol 12-myristate 13-acetate (PMA) at 1-100 nM, which inhibited CDP and reduced procollagen alpha 1(I) mRNA levels to a similar extent. The effects of IL-1 and PMA were independent of prostaglandin production, since indomethacin did not alter the inhibitory effect of either agent on CDP. Neither IL-1 (up to 10 ng/ml) nor PMA (100 nM) affected adenylate cyclase activity, while forskolin (10 microM), PTH (10 nM) and prostaglandin E2 (1 microM) stimulated adenylate cyclase activity 3- to 5-fold. However, forskolin (10 microM) and (Bu)2cAMP (100 microM) failed to alter CDP or procollagen alpha 1(I) mRNA levels. IL-1 (1 ng/ml) and PMA (100 nM) reduced transcription of the alpha 1(I) procollagen gene by 70% and 80%, respectively, while alpha 2(I) transcription was decreased by 59% and 53%. Neither IL-1 nor PMA affected transcription of the beta-actin or beta-tubulin genes.(ABSTRACT TRUNCATED AT 250 WORDS)
Mol Endocrinol 1990 Feb
PMID:Interleukin-1 alpha and phorbol ester inhibit collagen synthesis in osteoblastic MC3T3-E1 cells by a transcriptional mechanism. 232 98

Previous studies have shown that external calcium (Ca2+) is required for the effects of angiotensin II (AII) on aldosterone secretion in adrenal glomerulosa zone. Using bovine adrenal glomerulosa cells prepared by collagenase dispersion, we examined whether external Ca2+ is required for the activation of phospholipase C by AII. Adrenal glomerulosa cells were exposed to Ca-EGTA buffered media to provide accurate estimates of external free Ca2+ concentrations. Phospholipase C activation was evaluated by measurement of inositol phosphates production. At 0.1 microM Ca2+ and less, sustained AII effects on inositol monophosphate (IP), inositol bisphosphate (IP2) and inositol trisphosphate (IP3) were markedly inhibited. Increasing the Ca2+ concentration to 50 microM or greater fully restored AII-induced inositol phosphates production. AII-induced increases in cytosolic Ca2+ measured by Quin-2 fluorescence, were diminished at lower external Ca2+ concentrations. Treating adrenal glomerulosa cells with Chelex-100, a strong Ca2+ binding resin, blocked early activation of phospholipase C by AII. Inhibition of IP3 production was also observed when inhibitors of Ca2+ movement across the plasma membrane were used, viz., La2+, TMB-8 and nifedipine. The requirement for Ca2+ during AII-induced activation of phospholipase C may be explained, at least partly by a requirement for Ca2+ at a site between the AII receptor and Phospholipase C.
Mol Cell Biochem 1990 Jun 25
PMID:External calcium is required for activation of phospholipase C by angiotensin II in adrenal glomerulosa cells. 236 56

Rat thyroid follicles were isolated by collagenase digestion and cultured in suspension on agarose for 1-12 days with 0-0.1-1 mU/ml thyrotropin (TSH). After a 4 h exposure to Na125I they were processed for light and electron microscopy, autoradiography and biochemical analysis. Follicular 125I accumulation (A) and organification (PBI) were measured. Thyroglobulin (Tg) content of follicles and 125I-labelled amino acids in Tg were analyzed by high-performance liquid chromatography (HPLC). Without TSH, follicular lumina and cell polarity persisted. From day 3, the rough endoplasmic reticulum (RER) and ribosomes disappeared while autophagic vacuoles appeared: 125I accumulation and PBI were significantly reduced. From day 6, ultrastructural cell dedifferentiation occurred. At day 12, autoradiographic labelling was found over very few lumina; half of the 125I accumulated was still organified. With 1 mU TSH, follicles formed aggregates with narrow densely labelled lumina lined by tall cells. The RER was well developed up to day 12. 125I accumulation, PBI and iodothyronine (T3, T4) formation in Tg remained significantly higher than in follicles cultured without TSH, showing a transient decrease at days 6 and 9. Monoiodotyrosine/diiodotyrosine (MIT/DIT) and T3/T4 ratios in Tg were not modified, suggesting the persistence in the follicles of a significant iodine pool available for iodination. With 0.1 mU TSH, alterations of cell morphology and reduction of functional properties occurred later than without TSH. In the presence of TSH, morphological signs of new follicle formation were seen. These data demonstrate that closed follicles keep their follicular structure up to 12 days of culture, even without TSH. However, TSH is necessary to maintain iodine accumulation and organification.
Mol Cell Endocrinol 1990 Jun 18
PMID:Correlated morphological and functional study of isolated rat thyroid follicles in suspension culture. 237 85

We examined the ability of two filarial species, Onchocerca volvulus and Brugia malayi, to solubilize collagen molecules from native collagen fibrils. Collagenolytic activity was detected in extracts of adult worms, in living microfilariae of O. volvulus and in live infective larvae and adult female worms of B. malayi. Excretion-secretion factors produced in vitro by infective larvae of B. malayi also contained large amounts of collagenase. Studies with enzyme inhibitors suggest that the latter may be a metallo-protease. Antibodies to filarial collagenase were present in sera from patients with onchocerciasis and brugian filariasis and from mice immunized with B. malayi. These antibodies and a monoclonal antibody raised against O. volvulus antigens immunoprecipitate filarial collagenase but appear not to be directed against the active site of the enzyme.
Mol Biochem Parasitol 1986 Apr
PMID:Studies on a filarial antigen with collagenase activity. 242 72

Previous experiments showed that the presence of high levels of acute phase reactants (APR) enhance CCl4-induced liver fibrosis in the rat. A high correlation was found between the degree of fibrosis and alpha 2-macroglobulin of the rat (alpha 2-macrofetoprotein, alpha M-FP) used for monitoring the acute phase response. This acute phase reaction was provoked by epinephrine just before CCl4 treatment was started. In the present study we analyzed the effect of APR by repeating these experiments and estimating liver neutral collagenase with a synthetic substrate and endogenous collagen as a substrate, and liver prolyl-4-hydroxylase. A strong depression of liver collagenase activity was found in rats with a preceding acute phase reaction contrary to the rats that underwent CCl4 treatment only. A high level of alpha M-FP correlated negatively with collagenase activity. Also in vitro alpha M-FP proved to inhibit collagenase activity. Prolyl-4-hydroxylase was increased in the rats during acute phase reaction and correlated highly and positively with alpha M-FP, haptoglobin, and ceruloplasmin. Thus high levels of APR promote development of CCl4-induced fibrosis, partly by anticollagenase activity and partly because of enhancement of prolyl-4-hydroxylase activity. The latter phenomenon can also be explained by the presence of APR, but this has to be proved.
Exp Mol Pathol 1986 Oct
PMID:Mechanisms by which acute phase proteins enhance development of liver fibrosis: effects on collagenase and prolyl-4-hydroxylase activity in the rat liver. 242 60

Radiolabeled neurotoxins have been used to study the structure and function of sodium channels. We studied the binding of [3H] batrachotoxinin A 20 alpha-benzoate [( 3H]BTX-B) to specific sites on sodium channels on rat cardiac myocytes. Calcium-tolerant myocytes were prepared by collagenase dispersion of adult rat hearts and were 75-83% viable. As with the nerve channel, specific binding of [3H]BTX-B to its receptor site was seen only in the presence of sea anemone toxin (ATX). The affinity of ATX for its binding sites may be estimated from its concentration-dependent stimulatory effect on [3H]BTX-B binding. These results suggest that, in the presence of 5.4 mM KCl, the myocytes have two affinities for ATX with estimated dissociation constants of 0.52 microM and 12.9 microM. Depolarization of the myocytes with either 65 mM KCl or 0.1 mM BaCl2 results in the loss of the 0.52 microM component, suggesting that it is voltage sensitive. The 0.52 microM and 12.9 microM components have maximal binding capacities corresponding to 4 and 11 sites/micron 2 of myocyte surface area, respectively. Scatchard analysis of [3H]BTX-B binding in the presence of ATX demonstrates a single class of sites with a KD of 25-35 nM. These results demonstrate that [3H]BTX-B can be used as a radioligand probe of the adult rat sodium channel and will facilitate a biochemical approach to the study of the interaction between antiarrhythmic drugs and the sodium channel.
Mol Pharmacol 1986 Dec
PMID:Binding of [3H]batrachotoxinin A benzoate to specific sites on rat cardiac sodium channels. 243 Dec 64

In order to study human bile duct cells in vitro, cystic ducts were obtained during cholecystectomy and treated with collagenase and mechanical abrasion to isolate biliary epithelial cells. The culture medium was supplemented with 50% of a bovine bile duct conditioned medium obtained by incubating minced bovine extrahepatic bile ducts for 24 hr in Dulbecco's modified Eagle's medium. Cells grew in monolayer and showed contact inhibition at confluency. The epithelial origin of primary cultures was verified by their growth pattern, ultrastructure, and indirect immunofluorescence for cytokeratin. The cultures showed specific immunofluorescence for lysozyme, collagen types I, III, and IV, fibronectin, and laminin, but were negative for collagen type V and factor VIII-associated antigen. Thus, these cultures provide an experimental model for the in vitro study of biliary atresia and other bile duct diseases.
Exp Mol Pathol 1988 Jun
PMID:Characterization of human extrahepatic biliary duct epithelial cells in culture. 245 76


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