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Tissue factor pathway inhibitor (TFPI) is a factor Xa-dependent inhibitor for the factor VIIa-tissue factor complex. We isolated cDNA for rat TFPI by screening a lambda gt10 rat liver cDNA library. We determined the 1,228 bp nucleotide sequence, comprising a 88 bp 5' non-coding region, a 906 bp open reading frame, and a 234 bp 3' non-coding region, which encodes a protein of 302 amino acid residues. On Northern blot analysis of rat TFPI mRNA, rat TFPI mRNA was detected as two forms with different molecular sizes, 4.0 and 1.4 kb, which were expressed abundantly in heart, lung, kidney, and aortic endothelial cells. The homology of the amino acid sequence of rat TFPI with those of human and rabbit TFPI was found to be 60.7 and 57.4%, respectively. The lengths of the three tandem Kunitz-type inhibitor domains were strictly conserved not only among TFPI from the three species, but also among other proteins containing Kunitz-type inhibitor domains. The homology of the Kunitz-type domains in TFPI among the three species was 57, 86, and 69% in the 1st, 2nd, and 3rd domains, respectively. There was no significant difference in hydropathy profiles of TFPI from man, rabbit, and rat.  相似文献   
23.
Protein phosphatase (PP2B) whose activity is stimulated 12-20-fold by Ca2+/calmodulin (CaM) was partially purified by CaM-Sepharose and heparin-agarose chromatographies from cell extract of the yeast Saccharomyces cerevisiae. PP2B activity was not detectable in a mutant in which two genes (CMP1 and CMP2) encoding homologs of mammalian PP2B catalytic subunit were disrupted. We have previously shown that the double gene disruption has no significant effect on the growth of yeast [1991, Mol. Gen. Genet. 227, 52-59]. The results indicated that CMP1 and CMP2 are the only genes that encode the PP2B catalytic polypeptide in S. cerevisiae, and PP2B activity is not essential for the growth of the yeast under normal conditions.  相似文献   
24.
This paper presents the characterization of nine alleles of myospheroid, which encodes the beta PS subunit of the Drosophila PS integrins. On Southern blots, the mysXB87, mysXN101 and mysXR04 genes yield restriction digest patterns similar to that seen for wild-type chromosomes, however the mys1 and mysXG43 genes contain detectable deletions. mys1, mysXB87 and mysXG43 make little or no stable protein product, and genetically behave as strong lethal alleles. For the mysXN101 mutation, protein product is seen on immunoblots and a reduced amount of beta PS protein is seen at muscle attachment sites of embryos; this mutant protein retains some wild-type function, as revealed by complementation tests with weak alleles. Protein is also seen on immunoblots from mysXR04 embryos, and this allele behaves as an antimorph, being more deleterious in some crosses than the complete deficiency for the locus. mysts2 and mysnj42 are typically lethal in various combinations with other alleles at high temperatures only, but even at high physiological temperatures, neither appears to eliminate gene function completely. The complementation behaviors of mysts1 and mysts3 are quite unusual and suggest that these mutations involve regulatory phenomena. For mysts3, the data are most easily explained by postulating transvection effects at the locus. The results for mysts1 are less straightforward, but point to the possibility of a chromosome pairing-dependent negative interaction.  相似文献   
25.
Enzymatic degradation processes of microbial copolyesters, poly(3-hydroxybutyrate-co-3-hydroxyvalerate): P(3HB-co-3HV) and poly(3-hydroxybutyrate-co-4-hydroxybutyrate): P(3HB-co-4HB), were studied by the weight loss (erosion) of copolyester films. These studies employed three extracellular depolymerases which degrade poly(3-hydroxybutyrate): P(3HB). Two enzymes were purified from the culture supernatant of Pseudomonas lemoignei and one from Alcaligenes faecalis T1. The rate of enzymatic degradation of microbial copolyester films with various compositions showed an almost similar tendency to three different P(3HB) depolymerases, and decreased in the following order: P(3HB-co-4HB) greater than P(3HB) greater than P(3HB-co-3HV). An inhibitory protein of P(3HB) depolymerases in the succinate culture medium of P. lemoignei was isolated and characterized. The molecular weight of P(3HB) depolymerase inhibitor was 35,000 as determined by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate. This inhibitor of a single polypeptide chain may reversibly bind the serine residues at the active site of P(3HB) depolymerase. This inhibitory protein was not induced in the culture medium when P. lemoignei was grown on P(3HB) as the sole carbon source.  相似文献   
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The electron transport system (with cytochrome aa3) coupled to the oxidation of methanol in Methylobacterium extorquens AM1 (former Pseudomonas AM1) was reconstituted with highly purified constituents of the system. A mixture of 2.7 microM methanol dehydrogenase, 3.2 microM cytochrome cH, and 71 nM cytochrome c oxidase (= cytochrome aa3) consumed oxygen at a lower rate in the presence of methanol, while its activity was enhanced 3-fold by the addition of 1.4 microM cytochrome cL (74 mol of O2 consumed/mol of heme a of cytochrome c oxidase per min). Further addition of amicyanin to the above mixture did not affect the activity. Although ammonium ion greatly activated the activity of methanol dehydrogenase, the ion had little effect on the oxygen consumption activity of the above mixture. On the basis of the results obtained in the present study, an electron transport system is proposed for the oxidation of methanol in M. extorquens AM1.  相似文献   
28.
A study relating to gastrin release from gastrinoma cells by neuromedin B and C-terminal decapeptide of gastrin releasing peptide (GRP-10) has not yet been reported. Therefore, we studied the effects of neuromedin B and GRP-10 on gastrin release from cultured dispersed cells prepared from both the primary tumor in the pancreas and the metastatic tumor in the liver from a case of malignant Zollinger-Ellison syndrome. Both the primary and metastatic tumors obtained by a curative operation contained similar concentrations of gastrin and glucagon, whereas the primary tumor contained 10 times more insulin than the metastatic tumor. Gastrin release from cultured cells of both tumors was suppressed by 0.1 and 10 nM neuromedin B and tended to be suppressed by 0.1-10 nM GRP-10. However, insulin release from cultured cells of the pancreatic tumor was stimulated by GRP-10, but not by neuromedin B. These results might suggest that receptor function for the bombesin family peptides is abnormal in gastrinoma cells in both primary and metastatic tumors, and that a major source of insulin secretary cells is the contaminated normal islet cells in the primary tumor.  相似文献   
29.
The integration patterns of persisting adenovirus type 12 (Ad12) DNA were analyzed in two Ad12-induced tumors of Balb/c and CBA/J mice and in one tumor cell line derived from an Ad12-induced retinoblastoma of C3H origin. In all three tumors the Ad12 genome was integrated colinearly and various copy numbers of viral DNA were found. Analysis of the Ad12 integration patterns revealed relatively simple offsize band patterns regardless of Ad12 copy numbers. The degree of methylation at the 5''-CCGG-3'' sites in the inserted Ad12 genome was determined using the isoschizomeric restriction endonuclease pair HpaII and MspI. Methylation was rather incomplete in the primary tumor tissues but almost complete in the retinoblastoma line carried in culture for many passages. The levels of expression of the viral genome in the Balb/c tumor and in the retinoblastoma line were determined by in vitro translation of RNA isolated from these cells and selected with appropriate restriction endonuclease fragments of Ad12 DNA. In both instances the 59 K, 19 K, and 17 K proteins of the E1b region were expressed. Proteins of the E1a region appeared very faint in the size class between 22 K and 42 K. The permissivity of Ad12 and the replication of Ad12 DNA in mouse cells were investigated by blotting restricted DNA from cells soon after, and a long time after, infection and by hybridization with 32P-labeled Ad12 DNA. Neither primary mouse kidney cells nor the established L929 mouse cell line supported viral DNA replication. These results raise the question to what extent host cell factors determine Ad12 DNA replication in mammalian cells.  相似文献   
30.
Summary The 100 or so most intensely Coomassie blue-stained polypeptides from PHA-stimulated peripheral blood lymphocytes were analyzed by two-dimensional electrophoresis in combination with family and population studies. Besides polymorphic lymphocyte cytosol 64k polypeptide reported previously, genetic variants were frequently observed in three polypeptides with molecular weights of 100,000, 49,000, and 40,000. All of them occur in the cytosol. These variant polypeptides are charge variants, because they are separated in the isoelectric focusing dimension. It is indicated by family and population studies and cell distribution analysis that the polypeptide with a molecular weight of 100,000 shows a genetic polymorphism determined by two alleles at a new autosomal locus, as described in the following paper. Family and population studies also suggest that a genetic polymorphism defined by alleles at an autosomal locus is present in each of the polypeptides with molecular weights of 49,000 and 40,000. In contrast to the previous reports of the extremely restricted genetic variability of the 100 or so most abundant fibroblast polypeptides, the present data indicate that common genetic variants are present at least in four of the 100 or so most intensely Coomassie blue-stained lymphocyte polypeptides. The result also shows that careful side-by-side comparison of two-dimensional electrophoresis patterns among both parents and their children is an effective method to detect genetic variant polypeptides.  相似文献   
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