Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. We have found that 'acid'-activation of inactive human plasma renin is a two-phase process. About 30% of activation occurs during dialysis to pH 3.3; the remaining 70% occurs at alkaline pH. 2. The 'alkaline phase' of activation has a pH optimum between 7.5 and 8.4. It is inhibited by unacidified plasma and by soya-bean or lima-bean trypsin inhibitors. 3. 'Cryoactivation' of inactive plasma renin, which occurs at -4 degrees C and alkaline pH, is also inhibited by soya-bean or lima-bean trypsin inhibitors and by the serine protease inhibitors diisopropylphosphorofluoridate and benzamidine. 4. Thus endogenous neutral serine proteases participate in the activation of inactive plasma renin in vitro. Their action is prevented in the circulation by inhibitors which are inactivated by acid or cold.
Clin Sci Mol Med Suppl 1978 Dec
PMID:Activation of inactive plasma renin: evidence that both cryoactivation and acid-activation work by liberating a neutral serine protease from endogenous inhibitors. 3 4

1. Eight hypertensive patients with angina pectoris had placebo added to their existing medications for 8 weeks, then incremental doses of active labetalol with simultaneous stepwise reduction in other medicines until blood pressure was satisfactorily controlled; after that only labetalol and thiazide (8 weeks) and finally labetalol-placebo together with previous beta-adrenoreceptor antagonists and thiazide for 4 weeks were administered. 2. During the labetalol plus thiazide period resting blood pressures and measurements obtained during isotonic exercise, isometric exercise and the cold pressor test were significantly lower than during the initial placebo addition period. Angina scores were significantly reduced during this period. 3. During the final treatment with placebo, beta-adrenoreceptor antagonist and thiazide, blood pressures remained reduced, but angina was significantly worse. 4. Labetalol which antagonizes both alpha- and beta-adrenoreceptors produced better relief of angina pectoris than beta-adrenoreceptor antagonists during improvement in blood pressure in hypertensive patients.
Clin Sci Mol Med Suppl 1978 Dec
PMID:Labetalol in hypertensive patients with angina pectoris: beneficial effect of combined alpha- and beta-adrenoreceptor blockade. 3 6

The extranuclear mitochondrial oligomycin-resistant mutation of Aspergillus nidulans, (oliA1), was transferred asexually into four nuclear oligomycin-resistant strains of different phenotypes. In all four cases, the possession of the nuclear plus extranuclear mutation led to an increase in the in vivo level of oligomycin resistance. In two cases, the altered cytochrome spectrum and impaired growth ability determined by (oliA1) were suppressed by the nuclear mutations. In the third case, the in vitro oligomycin resistance of the double mutant ATPase was dramatically increased above that of either of the component single mutant strains, indicating a synergystic interaction between the nuclear and extranuclear gene products. In the fourth case, the double mutant became cold-sensitive. A new extranuclear mitochondrial oligomycin-resistant mutation (oliB332) is described. This mutant is phenotypically similar to, though not identical with, (oliA1) but is separable by recombination. A range of nuclear oligomycin-resistant mutants have been mapped. Despite presenting five distinctly different phenotypes, they all map at the same locus.
Mol Gen Genet 1977 Sep 09
PMID:Nuclear-extranuclear interactions affecting oligomycin resistance in Aspergillus nidulans. 14 64

The regulation of protein synthesis by steroids is thought to be due to hormonal effects primarily on mRNA concentration. Experimental evidence to support this conclusion has come largely from the use of DNA probes complementary (cDNA) to mRNA molecules or by translation of the mRNA in vitro. In this review the experimental procedures involved and the application to hormone action of cDNA hybridization will be reviewed. (1) mRNA concentrations can be assayed in tissue RNA samples by hybridization with radiolabelled complementary DNA probes (cDNA). From the rate of hybridization of an mRNA preparation to a cDNA probe it is possible to estimate specific mRNA concentrations and thereby study their hormonal regulation within tissues of subcellular fractions (2) Rates of synthesis of a specific RNA can be measured by hybridization of pulse-labelled RNA with excess cold cDNA as illustrated in studies of the glucocorticoid induction of MMTV RNA. (3) Hormore-induced alterations of mRNA populations as a whole can be investigated. From the kinetics of hybridization of mRNA with its complementary DNA it is possible to estimate the number of different RNA sequences in tissues and to approximate the number of copies of each sequence per cell. Consequently, by comparing mRNA samples isolated from tissues of different hormonal status it is possible to demonstrate specific hormone-inducible mRNA species and, in some cases, identify their translation products.
Mol Cell Endocrinol 1978 Apr
PMID:Hormonal control of mRNA synthesis studied by nucleic acid hybridization. 20 3

In order to find new genetic loci and functions on the yeast mitochondrial DNA, especially mutations affecting the mitochondrial protein synthesis apparatus, temperature sensitive mutants have been isolated after MnCl2 mutagenesis and mitochondrial and nuclear mutants classified according to their pattern of recombination with three rho- tester strains. Eighteen cold- and heat-sensitive respiratory deficient mitochondrial mutants have been isolated and localized on the mitochondrial genome by deletion mapping using 113 rho- strains. Eight of them appear to represent new loci, among which some are probably mutations of the tRNA and rRNA genes.
Mol Gen Genet 1977 Apr 29
PMID:Temperature-sensitive respiratory-deficient mitochondrial mutations: isolation and genetic mapping. 32 84

26 cold-resistant revertants of a cold-sensitive Escherichia coli mutant with an altered ribosomal protein S8 were analyzed for their ribosomal protein pattern by two-dimensional polyacrylamide gel electrophoresis. It was found that 16 of them had acquired the apparent wild-type form of protein S8, one exhibits a more strongly altered SC than the original mutant and two revertants regained the wildtype form of S8 and, in addition, possess alterations in protein L30. The ribosomes of the residual revertants showed no detectable difference from those of the parental S8 mutant. The mutation leading to the more strongly altered S8 was genetically not separable from the primary S8 mutation; this indicates that both mutations are very close to each other or at the same site. The structural gene for ribosomal protein L30 was mapped relative to two other ribosomal protein genes (for proteins S5 and S8) by the aid of one of the L30 mutants: The relative order obtained is: aroE....rpmD(L30)....rpsE(S5)....rpsH(S8)....rpsL(S12). The L30 mutation impairs growth and ribosomal assembly at 20 degrees C and is therefore the first example of a mutant with defined 50S alteration that has (partial) cold-sensitive ribosome assembly. A double mutant was constructed which possesses both the S8 and the L30 mutations. It was found that the L30 mutation had a slight antagonistic effect on the growth inhibition caused by the S8 mutation. Thus the L30 mutants might have possibly arisen from the original S8 mutant first as S8/L30 double mutants which was followed by the loss of the original S8 lesion.
Mol Gen Genet 1977 Apr 29
PMID:Cold-sensitive growth of a mutant of Escherichia coli with an altered ribosomal protein S8: analysis of revertants. 32 86

Among temperature resistant revertants of a temperature sensitive E. Coli alanyl-tRNA synthetase mutant a strain was found which contains an alanyl-tRNA synthetase with an additional mutation in the structural gene of the enzyme. This mutant enzyme has a 9 or 38 fold decreased Km value for alanine compared to that of the thermolabile parental enzyme or to wild-type enzyme, respectively. The alaS gene maps just counterclockwise from recA on the E. coli map (94% cotransduction frequency). It appears that the enzyme's increased affinity for alanine is the mechanism of suppressing the temperature sensitive character of the cell. In addition, some cold-sensitive temperature resistant revertants were found, where the cold-sensitive character mapped near strA. Presumably they are due to changes in ribosomal proteins as characterized by Ruffler et al. (1974).
Mol Gen Genet 1977 Nov 14
PMID:Suppression of a defective alanyl-tRNA synthetase in Escherichia coli: a compensatory mutation to high alanine affinity. 34 Sep 3

A mutation at a new locus denoted tsr1 which lies very close to the ery1 locus and 21S rRNA gene in mitochondrial DNA of Saccharomyces cerevisiae, confers conditional respiratory deficiency on cells grown at low temperature, namely 18 degrees. Studies on mitochondria isolated from a strain carrying the mutatated tsr1 locus demonstrate that the rate of mitochondrial protein synthesis is cold-senitive at 18 degrees. The large subunit of the mitochondrial ribosomes isolated from the mutant strain is unstable during extraction and the isolated ribosomes are shown to be defective in catalyzing the poly U-directed synthesis of polyphenylalanine. It is concluded that the tsr1 locus is involved in the determination of the properties of the large subunit of the mitochondrial ribosome.
Mol Biol Rep 1978 Jun 16
PMID:Altered mitochondrial ribosomes in a cold-sensitive mutant of Saccharomyces cerevisiae. 35 61

Plasmolysed cells of Escherichia coli N212 (uvr A recA) acquired ultraviolet resistance when the cells were exposed to high concentrations of T4 endonuclease V. With increasing concentrations of T4 enzyme, survivals of plasmolysed cells after ultraviolet irradiation increased while colony-forming ability of unirradiated plasmolysed cells was not significantly affected by the enzyme treatment. Under appropriate conditions more than 200 fold increase in survivals was observed. When plasmolysed cells were treated with a pre-heated enzyme preparation or enzyme fractions derived from T4v1 (endonuclease V-deficient mutant)-infected cells, only little or no reactivation took place. Permeabilization of cells prior to the enzyme treatment was essential for the effective reactivation. Treatment of intact cells with the T4 enzyme did not cause any reactivation. Cells treated with 20 mM EGTA or 50 mM CaCl2 in cold were reactivated to certain extents by the enzyme, but the extents of the reactivation were far less compared to those of plasmolysed cells. Plasmolysed cells of strains carrying a mutation in one of uvrA, uvrB and uvrC genes were reactivated by introduction of T4 endonuclease V, as was the uvrA recA double mutant. UvrD mutants were also reactivated, but rather slightly. However, wild type strain as well as strains having a mutation in recA or polA gene were not reactivated. From these results it was suggested that T4 endonuclease V, taken up into permeable cells, can function in vivo to replace defective functions, which are controlled by the uvr genes. The conditions established in the present study may be used for introduction of other proteins into viable bacterial cells.
Mol Gen Genet 1979 Jan 05
PMID:Introduction of an active enzyme into permeable cells of Escherichia coli: acquisition of ultraviolet light resistance by uvr mutants on introduction of T4 endonuclease V. 37 39

Two genes governing ribosomal protein methylation have been located on the map of Escherichia coli by conjugation and transduction crosses between wild-type and prm (protein methylation) mutants. The Prm phenotype of recombinants was determined by an in vitro assay of methylgroups incorporation into protein. Gene prmA, governing methylation of protein L11 is situated at minute 71 on the map and is cotransduced with aroE (30%) and with rpsL (5%). Gene prmB, governing methylation of protein L3 is at minute 50, very close to aroC (98.5% co-transduction). A cold-sensitive phenotype was found associated with mutation prmB and was used to score a large number of recombinants in a three factor cross. The results of this cross suggest the order aroC -prmB - purF. The striking symmetrical clustering of aro, prm and rim (ribosome maturation) genes is discussed.
Mol Gen Genet 1979 Feb 01
PMID:Genetics of ribosomal protein methylation in Escherichia coli. III. Map position of two genes, prmA and prmB, governing methylation of proteins L11 and L3. 37 46


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