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
Query: EC:3.4.21.4 (
trypsin
)
42,187
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Matrix-attachment regions (MARs) are DNA elements that are defined by their abilities to bind to isolated nuclear matrices in vitro. The DNA sequences of different matrix-binding elements vary widely. The locations of some MARs at the ends of chromatin loops suggest that they may represent boundaries of individual chromatin domains. As such, MARs may play important roles in regulating transcription and chromatin structure. As a first step towards assessing the roles of MARs in these processes, we assayed DNA sequences from the human
serine protease inhibitor
(serpin) gene cluster at 14q32.1 for matrix-binding activity in vitro. This approximately 150 kb region contains the cell-specific genes encoding alpha1-anti-
trypsin
(alpha1AT) and corticosteroid-binding globulin (CBG), as well as an antitrypsin-related sequence termed ATR. A DNase I-hypersensitive site (DHS) map of the locus has recently been described. We report here that the alpha1AT-ATR-CBG region contains five distinct MARs. There is a strong matrix-binding element approximately 16 kb upstream of alpha1AT; three MARs are between ATR and CBG and one MAR is within the CBG gene itself. These MARs were matrix-associated in all cell types examined. DNA sequencing indicated that the serpin MARs contained predominantly repetitive DNA, although the types of DNA repeats differed among the MARs.
...
PMID:Identification and characterization of nuclear matrix-attachment regions in the human serpin gene cluster at 14q32.1. 1048 Oct 16
Human tissue factor pathway inhibitor-2 (TFPI-2)/matrix-associated
serine protease inhibitor
(MSPI), a Kunitz-type serine protease inhibitor, inhibits plasmin,
trypsin
, chymotrypsin, plasma kallikrein, cathepsin G, and factor VIIa-tissue factor complex. The mature protein has a molecular mass of 32-33 kDa, but exists in vivo as two smaller, underglycosylated species of 31 and 27 kDa. TFPI-2/MSPI triplet is synthesized and secreted by a variety of cell types that include epithelial, endothelial, and mesenchymal cells. Because the majority (75-90%) of TFPI-2/MSPI is associated with the extracellular matrix (ECM), we examined which components of the ECM bind TFPI-2/MSPI. We found that TFPI-2/MSPI bound specifically to heparin and dermatan sulfate. Interaction of these two glycosaminoglycans (GAGs) with TFPI-2/MSPI involved one or more common protein domains, as evidenced by cross-competition experiments. However, binding affinity for TFPI-2/MSPI with heparin was 250-300 times greater than that for TFPI-2/MSPI with dermatan sulfate. Binding of TFPI-2/MSPI to GAGs was inhibited by NaCl or arginine but not by glucose, mannose, galactose, 6-aminohexanoic acid, or urea, suggesting that arginine-mediated ionic interactions participate in the GAG binding of TFPI-2/MSPI. This supposition was supported by the observation that only NaCl or arginine could elute the TFPI-2/MSPI protein triplet from an ECM derived from human dermal fibroblasts. Reduced TFPI-2/MSPI did not bind to heparin, suggesting that proper disulfide pairings and conformation are essential for matrix binding. To determine whether heparin modulates the activity of TFPI-2/MSPI, we determined the rate of inhibition of plasmin by the inhibitor with and without heparin and found that TFPI-2/MSPI is more active in the presence of heparin. Collectively, our results demonstrate that conformation-dependent arginine-mediated ionic interactions are responsible for the TFPI-2/MSPI triplet binding to fibroblast ECM, heparin, and dermatan sulfate and that heparin augmented the rate of inhibition of plasmin by TFPI-2/MSPI.
...
PMID:Matrix localization of tissue factor pathway inhibitor-2/matrix-associated serine protease inhibitor (TFPI-2/MSPI) involves arginine-mediated ionic interactions with heparin and dermatan sulfate: heparin accelerates the activity of TFPI-2/MSPI toward plasmin. 1049 84
Different subpopulations of mast cells are characterized by their abundant contents of either
tryptase
or in addition chymase. These two neutral proteases are found in mast cells and may thus hold a key to the understanding of mast cell dependent reactions. Such studies are however hampered by the lack of readily available supplies of chymase. We have therefore studied the simultaneous purification of both proteases from hairless moro hr/hr mouse skin, using a sequence of salt extractions and chromatographic separations. After three steps of extraction, a 13-fold purification with an 82% yield was obtained for
tryptase
and a 15-fold purification with a 90% yield for chymase. Further one step purification on conventional sephadex, sephacryl and octyl sepharose columns was unsatisfactory because of further protein contamination of the fractions. Heparin affinity chromatography caused a high loss of
tryptase
and residual protein contamination. Gradient elution on a benzamidine sepharose 6B column resulted however in a single, low yield (17.9%)
tryptase
peak and a broader, high yield (>90%) chymase peak, and a 34% yield high purity fraction. The proteases thus purified exhibited their typical inhibitor profile. On Western blot analysis and on autoradiography in the presence of the
serine protease inhibitor
diisopropylfluorophosphate (DFP), only one 28 kD molecule with chymase activity was identified, whereas a broad 32-38 kD band of
tryptase
monomers was noted. Taken together, these data show that, after salt extraction and a single benzamidine affinity chromatography step, both mast cell chymase and
tryptase
can be separated and in case of chymase also highly purified, allowing thus for the study of biological activities of this molecule.
...
PMID:Purification of mast cell proteases from murine skin. 1053 69
Latent mushroom tyrosinase can be considered as a zymogen when activated by proteases because the activation process fulfilled all of the kinetic dependencies predicted by a theoretical zymogen activation model previously reported. The activation was studied under two assay conditions: high and low ratio of latent tyrosinase/serine protease (
trypsin
and subtilisin Carlsberg) concentrations, in the presence and in the absence of a
serine protease inhibitor
(aprotinin). The size of the latent enzyme was 67 kDa, determined by denaturing SDS-PAGE electrophoresis and Western blot assays. After proteolytic activation, the size was 43 kDa, with an intermediate band of 58 kDa. The values of the catalytic () and Michaelis () constants for the active forms of tyrosinase resulting from the activation by subtilisin,
trypsin
, or sodium dodecyl sulfate on the substrate tert-butylcatechol were slightly different, which could support the idea of "one activator-one different active tyrosinase". Vacuum infiltration experiments tried to reproduce in vivo the role of mushroom serine proteases in the activation of latent tyrosinase. The use of serine protease inhibitors is proposed as a new alternative tool to prevent melanin formation.
...
PMID:Kinetic study of the activation process of a latent mushroom (Agaricus bisporus) tyrosinase by serine proteases. 1055 77
Blood serine protease inhibitors are becoming better understood and increasingly applied in blood clotting, cancer and other diseases. Reptiles are suitable models for blood coagulation and related processes, moreover, caiman is a good comparative model of a non-poisonous reptile. Recently, we reported the purification of a kininogen, the presence of proteases involved in blood clotting, and a
serine protease inhibitor
in Caiman crocodilus yacare plasma. In this paper, we described the partial sequence of an inhibitor (CcTI). The inhibitor is an 80-kDa protein, and it inactivates
trypsin
and chymotrypsin the hydrolysis of specific chromogenic substrates and in the degradation of gelatin. The inhibitor is member of Kazal-type inhibitor family and consists of several domains, its putative reactive site is Arg-His.
...
PMID:Preliminary characterization of a Kazal-type serine protease inhibitor from Caiman crocodilus yacare plasma. 1061 9
Close association exists between melanocytes, the pigment melanin-producing cells in the body, and their neighboring keratinocytes. Keratinocytes are the pigment recipients and skin pigmentation is the result of this interaction. While the chemical basis of melanin production (melanogenesis) is well documented, the molecular mechanism of melanosome transfer needs to be elucidated. We are now providing first evidence that the protease-activated receptor 2 (PAR-2) expressed on keratinocytes, but not on melanocytes, is involved in melanosome transfer and therefore may regulate pigmentation. Activation of PAR-2 with
trypsin
or with the peptide agonist SLIGRL induced pigmentation in both two- and three-dimensional cocultures of keratinocytes and melanocytes, but not in cocultures that were spatially separated, indicating the need for intimate cell-cell contact. Topical application of SLIGRL on human skin transplanted on SCID mice resulted in a visible skin darkening. Histological examination revealed increased deposits of melanin in the keratinocytes. Inhibition of PAR-2 activation by RWJ-50353, a
serine protease inhibitor
, resulted in depigmentation and changes in expression of melanogenic-specific genes. Keratinocyte-melanocyte contact was essential for this depigmenting effect. Topical application of this inhibitor induced lightening of the dark skin Yucatan swine, which was confirmed by histochemical analysis. The results presented here suggest a novel mechanism for the regulation of pigmentation, mediated by the activation or inhibition of the keratinocyte receptor PAR-2.
...
PMID:The protease-activated receptor 2 regulates pigmentation via keratinocyte-melanocyte interactions. 1062 62
alpha(1)-Protease inhibitor (alpha(1)PI), the most abundant
serine protease inhibitor
found in human plasma (at 30-60 microM), is a glycoprotein (53 kDa) having a single cysteine residue at position 232 (Cys(232)). We have found that Cys(232) of human alpha(1)PI was readily S-nitrosylated by nitric oxide (NO) without affecting inhibitory activity to
trypsin
or elastase. S-nitrosylated alpha(1)PI (S-NO-alpha(1)PI) not only retained inhibitory activity against these serine proteases, but also gained thiol protease inhibitory activity against a Streptococcus pyogenes protease; the parental alpha(1)PI did not have this activity. Furthermore, S-NO-alpha(1)PI exhibited bacteriostatic activity against Salmonella typhimurium at concentrations of 0.1-10 microM, which were 20- to 3000-fold stronger than those of the other NO-generating compounds or S-nitroso compounds such as S-nitrosoalbumin and S-nitrosoglutathione. NO appears to be transferred into the bacterial cells from S-NO-alpha(1)PI via transnitrosylation, as evidenced by electron spin resonance spectroscopy with an NO spin trap. Thus, we conclude that S-NO-alpha(1)PI may be generated from the reaction between alpha(1)PI and NO under inflammatory conditions, in which production of both is known to increase. As a result, new functions, i.e., antibacterial and thiol protease inhibitory activities of alpha(1)PI, were generated.
...
PMID:Novel functions of human alpha(1)-protease inhibitor after S-nitrosylation: inhibition of cysteine protease and antibacterial activity. 1067 91
Serpins define a large protein family in which most members function as serine protease inhibitors. Here we report the results of a search for serpins in Drosophila melanogaster that are potentially required for oogenesis or embryogenesis. We cloned and sequenced ovarian cDNAs that encode six distinct proteins having extensive sequence similarity to mammalian serpins, including residues important in the serpin inhibition mechanism. One of these new serpins in recombinant form inactivates, and complexes with,
trypsin
-like proteases in vitro. To our knowledge, these results represent the first evidence for a serpin in Drosophila that functions as a
serine protease inhibitor
.
...
PMID:A novel Drosophila serpin that inhibits serine proteases. 1069 85
The synthesis and design using molecular modeling techniques for non-peptide, low molecular weight novel fibrinogen receptor (glycoprotein IIb/IIIa: Gp IIb/IIIa) antagonists, is reported. We used a highly potent
serine protease inhibitor
, Nafamostat, having an amidinonaphthyl unit as the starting compound. The compounds 4-(6-amidino-2-naphthylaminocarbonyl)phenoxyacetic acid (5a) and 4-(6-amidino-2-naphthalenecarboxamido)phenoxyacetic acid (5b) inhibited adenosin-5'-diphospate (ADP)-induced aggregation of human platelet-rich plasma (PRP) with IC50 values of 0.05 and 0.07 microM, respectively, and had lost their ability to inhibit a variety of serine proteases, including thrombin, factor Xa, plasmin and
trypsin
.
...
PMID:Preparation and pharmacological evaluation of novel glycoprotein (Gp) IIb/IIIa antagonists. 1. The selection of naphthalene derivatives. 1074 13
Ecotin is a dimeric
serine protease inhibitor
from Escherichia coli which binds proteases to form a hetero-tetramer with three distinct interfaces: an ecotin-ecotin dimer interface, a larger primary ecotin-protease interface, and a smaller secondary ecotin-protease interface. The contributions of these interfaces to binding and inhibition are unequal. To investigate the contribution and adaptability of each interface, we have solved the structure of two mutant ecotin-
trypsin
complexes and compared them to the structure of the previously determined wild-type ecotin-
trypsin
complex. Wild-type ecotin has an affinity of 1 nM for
trypsin
, while the optimized mutant, ecotin Y69F, D70P, which was found using phage display technologies, inhibits rat
trypsin
with a K(i) value of 0.08 nM. Ecotin 67-70A, M84R which has four alanine substitutions in the ecotin-
trypsin
secondary binding site, along with the M84R mutation at the primary site, has a K(i) value against rat
trypsin
of 0.2 nM. The structure of the ecotin Y69F, D70P-
trypsin
complex shows minor structural changes in the ecotin-
trypsin
tetramer. The structure of the ecotin 67-70A, M84R mutant bound to
trypsin
shows large deviations in the tertiary and quaternary structure of the complex. The
trypsin
structure shows no significant changes, but the conformation of several loop regions of ecotin are altered, resulting in the secondary site releasing its hold on
trypsin
. The structure of several regions previously considered to be rigid is also significantly modified. The inherent flexibility of ecotin allows it to accommodate these mutations and still maintain tight binding through the compromises of the protein-protein interfaces in the ecotin-
trypsin
tetramer. A comparison with two recently described ecotin-like genes from other bacteria suggests that these structural and functional features are conserved in otherwise distant bacterial lineages.
...
PMID:Compromise and accommodation in ecotin, a dimeric macromolecular inhibitor of serine proteases. 1084 53
<< Previous
1
2
3
4
5
6
7
8
9
10
Next >>