Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.4.24.3 (collagenase)
18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Labial salivary glands are found in the majority of insects. They are relatively large, extend back into the thorax, and in Rhodnius, they are cherry red in color due to a pigment derived from traces of hemoglobin absorbed form the gut. In most insects they are acinous shaped, with long excretion channels that present differentiated regions which from salivary reservoirs. The glands may be relatively simple or complexly branched and convoluted. In Rhodnius they are described as being unilobed with no traces of division. The main duct leaves the gland at its anterior extremity. The acini have different kinds of cells but all of them are seen as sources of secretion. Our material has a different shape due to the fact that the animals spent 20 days under starvation conditions. New data are also obtained through treatment with collagenase and HCl. The importance of the study of these glands lies in the fact that it will further understanding of the transmission of Chagas' disease.
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PMID:Scanning electron microscopy of the Rhodnius neglectus (Hemiptera) labial salivary glands after starvation. 825 Feb 70

The structure of the extension peptides retained on the tissue form of type V collagen molecules was determined. Type V collagen alpha chains containing extension peptides were extracted from fetal calf skin and bone by 4 M guanidine-HCl and 0.5 M acetic acid, respectively. Collagens present in both extracts were fractionated by sodium chloride precipitation. The collagen alpha(V) chains were then resolved by reverse-phase high performance liquid chromatography. The N-terminal extension peptides were characterized by direct sequence analysis after deblocking with pyroglutamate amino-peptidase and analysis of the products of digestion by bacterial collagenase, chymotrypsin, V8 protease and endoproteinase Lys-C. The results showed that the retained extension peptides on type V collagen molecules in the extracellular matrix of skin and bone were amino-propeptides and that the alpha 2(V) chain retains an intact amino-propeptide while the alpha 1(V) chain appears to be partially processed. The extended alpha 1(V) chain isolated from fetal calf bone gave an identical amino-terminal sequence to that of the alpha 1(V) chain isolated from fetal calf skin, suggesting that a specific enzyme may be involved in processing the alpha 1(V) amino-propeptide.
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PMID:Structural analysis of the extension peptides on matrix forms of type V collagen in fetal calf bone and skin. 826 15

The tectorial membrane is a gel-like, acellular connective tissue overlying the microscopic organ of Corti--the auditory sensory structure. It is instrumental in the sound-synchronous deflection of the stereocilia of the hair cells, a central event in auditory transduction. It is well established that collagen, primarily type II, constitutes the major protein of the tectorial membrane, with smaller amounts of types IX and XI also present. However, conclusive information on the proteoglycans in this structure is lacking. Tectorial membranes were extracted with a 4 M guanidine--HCl solvent, and proteoglycans isolated after ethanol precipitation and collagenase treatment. A colorimetric assay based on the binding of the cationic dye safranin O to glycosaminoglycans, in combination with enzymatic techniques, detected significant amounts of chondroitin sulfate and keratan sulfate (0.29 and 0.17% on a wet weight basis, respectively). Agarose-polyacrylamide electrophoresis of chondroitinase-digested samples revealed a core protein with a similar molecular mass to that of the large cartilage proteoglycan aggrecan. This proteoglycan reacted with the antibody 3-B-3 (recognizing modified chondroitin 6-sulfate linkage region oligosaccharides). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed several low molecular mass proteins which reacted with 5-D-4, specific for keratan sulfate, one of which showed characteristics of fibromodulin. Comparison of the quantitative aspects of various connective tissue components of tectorial membrane with other type II collagen-containing structures revealed that this tissue resembles highly hydrated cartilage.
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PMID:Uronic acid-containing glycosaminoglycans and keratan sulfate are present in the tectorial membrane of the inner ear: functional implications. 827 27

Serotonin (5-hydroxytryptamine; 5-HT) has recently been shown to induce collagenase production in myometrial smooth muscle cells (Jeffrey et al. (1991) J. Cell. Physiol. 146, 399-406) by activating transcription of the collagenase gene (Wilcox et al. (1992) J. Biol. Chem. 267, 20752-20757) following an interaction with the 5-HT2 receptor (Rydelek-Fitzgerald et al. (1993) Mol. Cell. Endocrinol. 91, 67-74). These studies were performed to investigate factors controlling the regulation of 5-HT2 receptors in these cells. Northern blot analysis indicates that serotonin increases levels of 5-HT2 receptor mRNA in cells by approximately 4-fold. Detectable increases in mRNA levels occur within 2 h after administration of serotonin with maximal levels occurring after 12 h. The 5-HT2 receptor antagonists, ketanserin and spiperone, inhibit the serotonin-mediated increase in receptor mRNA. Selective 5-HT2 receptor agonists ((+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane HCl (DOI) and quipazine) mimic the effect of serotonin, whereas 5-HT1 and 5-HT3 receptor agonists ((+/-)-8-hydroxydipropylaminotetralin (8-OH-DPAT), 1-(3-chlorophenyl)piperazine dihydrochloride (mCPP), m-phenylbiguanide) have no effect. These data demonstrate that serotonin induces an increase in 5-HT2 receptor mRNA by interacting with the 5-HT2 receptor itself. Nuclear run-on analysis revealed that serotonin increases the initiation of 5-HT2 receptor mRNA synthesis. Moreover, the protein synthesis inhibitor, cycloheximide, prevents the induction of the mRNA for the receptor, demonstrating that serotonin-dependent increases in 5-HT2 receptor transcription require de novo protein synthesis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Serotonin-mediated 5-HT2 receptor gene regulation in rat myometrial smooth muscle cells. 831 29

Asymmetric forms of acetylcholinesterase (AChE) are thought to be the predominant forms of this enzyme at vertebrate neuromuscular junctions where they attach to the synaptic basal lamina via a collagen-like tail. High salt and heparin-containing buffers are capable of solubilizing asymmetric AChE molecules from skeletal muscle; however, detachment of AChE specifically from synaptic basal lamina using these procedures has not been demonstrated. To determine whether AChE can be solubilized from mature neuromuscular junctions, adult quail muscle fibers were extracted with buffered detergent solutions containing either 0.05 M NaCl, 1 m NaCl, 0.5-2 mg/ml heparin, 8 M urea, or 4 m guanidine HCl, and the remaining AChE molecules were localized by indirect immunofluorescence. Analysis of extracted AChE oligomeric forms showed that low salt buffers containing heparin and high salt buffers were capable of solubilizing substantial amounts of catalytically active collagen-tailed AChE, whereas none of these buffers were capable of detaching AChE from synaptic basal lamina. In contrast, digestion with purified collagenase detached asymmetric forms from the non-extractable fraction and removed the AChE from the neuromuscular junctions. Parallel experiments using rat gastrocnemius muscle and enzyme histochemistry to detect AChE gave similar results. These studies indicate that the junctional AChE molecules are firmly attached to the extracellular matrix and that all the conventional extraction buffers used to solubilize the asymmetric collagen-tailed forms of AChE are incapable of detaching this enzyme from the synaptic basal lamina.
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PMID:Localization of "non-extractable" acetylcholinesterase to the vertebrate neuromuscular junction. 836 Jan 97

The mechanisms of organic matrix breakdown in the root caries process are not well understood. Therefore, the combined and separate effects of lactic acid and proteolytic enzymes on the degradation of human dentin collagen, glycoproteins, proteoglycans and phosphoproteins were investigated in the present study. Dentin powder was pretreated with lactic acid (pH 4.0), distilled and deionized (dd) water (pH 7.0) and EDTA/guanidine HCl (pH 7.4) for 24 h. Pellets of acid- or dd water-pretreated dentin powder were washed, dried, and then treated with trypsin, bacterial or mammalian tissue collagenase, or control buffer for 3 h. The released dentin proteins were analyzed by reducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting to identify degraded type I collagen, proteoglycans, glycoproteins and phosphoproteins. All water and acid pretreatment and enzyme treatment groups demonstrated two collagen fragment bands with molecular weights at approximately 79 kD. Further studies showed that the 79 kD proteins from acid-pretreated dentin collagen were degraded by tissue collagenase, suggesting that endogenous collagenase may be involved in the degradation of root dentin collagen. Dentin proteoglycans were detectable in all the treatment groups by protein slot blotting. Relatively few distinct glycoproteins and proteoglycans, and no phosphoproteins were detected by immunoblotting. Results from this study suggest that both acids and proteolytic enzymes from either host or microbial origin are important in the degradation of human dentin matrix and the mechanisms involved in the release of various noncollagenous proteins may be different.
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PMID:Effect of lactic acid and proteolytic enzymes on the release of organic matrix components from human root dentin. 855 53

Three-dimensional structures of the nerves of the guinea-pig gallbladder, after histochemical demonstration of the acetylcholinesterase activity and HCl hydrolysis-collagenase digestion, were examined by scanning electron microscope. HCl-collagenase digestion facilitated easy identification of silver- and gold-intensified acetylcholinesterase-positive nerve fibers at a high accelerating voltage (25 kV), due to their strong reflection image. Ganglia were either triangular or ovoidal in shape. Dense para- and peri-vascular nerve fibers occurred around the cystic artery. There were a few intramuscular nerve fibers with varicosity-like structures among smooth muscle bundles. Dense branched and tapering nerve fibers with varicosities in the lamina propria mucosae were closely attached to epithelial cells. The acetylcholinesterase-positive fibers in the lamina propria and peri- and para-vascular nerves, and fewer positive fibers in the smooth muscle layer probably represent cholinergic nerves involved in the concentration of biliary compounds and lesser in the motor function of the smooth muscle.
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PMID:Scanning electron microscopic observations of nerves in the guinea-pig gallbladder after an acetylcholinesterase histochemistry. 858 3

We evaluated the mechanism of increased serum concentrations of the 7S fragment of the N-terminal domain of type IV collagen (7S collagen) in chronic liver disease. We measured the concentrations of hepatic-free and deposited 7S collagens after extraction with Tris-HCl buffer and bacterial collagenase, then compared them with the serum levels in 8 normal controls and 48 patients with chronic liver disease. The hepatic 7S collagen levels extracted with Tris-HCl buffer and collagenase accounted for 7% and 93%, respectively, of the total 7S collagen levels in normal controls. Both hepatic 7S collagen levels as well as serum levels increased in accordance with the progress of liver disease. Serum levels of 7S collagen showed a closer correlation with the hepatic 7S collagen levels extracted with Tris-HCl buffer (r = .822), compared with those extracted with collagenase (r = .382). On the other hand, the histological degrees of liver fibrosis were highly correlated with the hepatic collagenase-extracted 7S collagen levels (r = .822), compared with serum and the hepatic Tris-HCl buffer-extracted levels (r = .478 and r = .537, respectively). Although there was no difference in serum and hepatic 7S collagen levels between B and C viral patients, the serum and hepatic Tris-HCl buffer-extracted 7S collagen levels were higher in patients with alcoholic cirrhosis than patients with viral cirrhosis. However, the hepatic collagenase-extracted levels were similar in both groups. Gel filtration demonstrated that the serum and hepatic Tris-HCl buffer-extracted 7S collagens were mainly eluted in the macromolecular 7S collagen-reactive fraction in cirrhosis, whereas the hepatic collagenase-extracted 7S collagen was eluted in the authentic 7S collagen-reactive fraction. The results suggest that serum 7S collagen levels are not a particularly reliable measure of hepatic fibrosis but reflect the enhanced metabolism, especially synthesis of type IV collagen in the liver.
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PMID:Relationship between serum and hepatic 7S fragments of type IV collagen in chronic liver disease. 862 Nov 48

Recombinant interstitial collagenase (rMMP-1) forms insoluble inclusion bodies when over-expressed in Escherichia coli. We surveyed conditions for renaturation of purified rMMP-1 in 6 M guandine hydrochloride (GdnHCl) and found that optimal folding occurred when the denatured protein was diluted at 4 degrees C in approximately 2 M guanidine HCl, 20% glycerol, 2.5 mM reduced and oxidized glutathione, and 5 mM CaCl2, followed by buffer exchange to remove denaturant and thiols. The circular dichroism spectrum and catalytic constants of the refolded enzyme were similar to those of native MMP-1. The propeptide, which comprises approximately 20% of the mass of proMMP-1, was not required for folding to a functional enzyme. Size exclusion chromatography and spectroscopic measurements at intermediate [GdnHCl] revealed two intermediate folding states. The first, observed at 1 M GdnHCl, had a slightly larger Stokes' radius than the folded protein. CD and fluorescence analysis showed that it contained ordered tryptophan residues with a higher quantum yield than the fully folded state. The second intermediate, which appeared between 2 and 4 M GdnHCl, exhibited properties consistent with the molten globule, including secondary structure, lack of ordered tryptophan, exposed hydrophobic binding sites, and a Stokes' radius between that of the folded and unfolded states.
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PMID:Characterization of folded, intermediate, and unfolded states of recombinant human interstitial collagenase. 862 83

Although it is well accepted that implant success is dependent on various surface properties, little is known about the effect of surface roughness on cell metabolism or differentiation, or whether the effects vary with the maturational state of the cells interacting with the implant. In the current study, we examined the effect of titanium (Ti) surface roughness on chondrocyte proliferation, differentiation, and matrix synthesis using cells derived from known stages of endochondral development. Chondrocytes derived from the resting zone (RCs) and growth zone (GCs) of rat costochondral cartilage were cultured on Ti disks that were prepared as follows: HF-HNO3-treated and washed (PT); PT-treated and electropolished (EP); fine sand-blasted, HCl-H2SO4-etched, and washed (FA); coarse sand-blasted, HCl-H2SO4-etched, and washed (CA); or Ti plasma-sprayed (TPS). Based on surface analysis, the Ti surfaces were ranked from smoothest to roughest: EP, PT, FA, CA, and TPS. Cell proliferation was assessed by cell number and [3H]-thymidine incorporation, and RNA synthesis was assessed by [3H]-uridine incorporation. Differentiation was determined by alkaline phosphatase specific activity (AL-Pase). Matrix production was measured by [3H]-proline incorporation into collagenase-digestible (CDP) and noncollagenase-digestible (NCP) protein and by [35S]-sulfate incorporation into proteoglycan. GCs required two trypsinizations for complete removal from the culture disks; the number of cells released by the first trypsinization was generally decreased with increasing surface roughness while that released by the second trypsinization was increased. In RC cultures, cell number was similarly decreased on the rougher surfaces; only minimal numbers of RCs were released by a second trypsinization. [3H]-thymidine incorporation by RCs decreased with increasing surface roughness while that by GCs was increased. [3H]-Uridine incorporation by both GCs and RCs was greater on rough surfaces. Conversely, ALPase in the cell layer and isolated cells of both cell types was significantly decreased. GC CDP and NCP production was significantly decreased on rough surfaces while CDP production by RC cells was significantly decreased on smooth surfaces. [35S]-sulfate incorporation by RCs and GCs was decreased on all surfaces compared to tissue culture plastic. The results of this study indicate that surface roughness affects chondrocyte proliferation, differentiation, and matrix synthesis, and that this regulation is cell maturation dependent.
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PMID:Effect of titanium surface roughness on chondrocyte proliferation, matrix production, and differentiation depends on the state of cell maturation. 901 78


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