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)

Amylase from chicken pancreas was purified by an affinity method involving filtering a crude extract from pancreas through a Sepharose-wheat albumin column and eluting the retained enzyme with maltose. The purified amylase showed two active bands upon polyacrylamide electrophoresis in an alkaline buffer system and only one band in an acidic buffer system. The enzyme is a Ca2+-glycoprotein which behaves as a typical alpha-amylase. It consists of a single polypeptide chain with molecular weight 53,000 and contains 5.3 moles of reducing sugars per mole of protein. Optimal conditions of pH and temperature for the enzymic activity are 7.5 and 37 degrees C. The enzyme is irreversibly inactivated by removal of Ca2+ by exhaustive dialysis and is activated by the presence in the assay mixture of Cl-; other halides are less effective than Cl- in activating the enzyme.
Mol Cell Biochem 1977 Aug 19
PMID:Purification and properties of alpha-amylase from chicken (Gallus gallus L.) pancreas. 2 May 68

1. Plasma membrane preparations have been isolated from spheroplasts of Saccharomyces cerevisiae, strain R XII, via lysis and subsequent differential centrifugation. These preparations are almost devoid of mitochondrial contamination. 2. The plasma membrane ATPase is fairly stable when refrigerated, but loses activity at 8 degrees C and above. Below pH 5.6 the ATPase is irreversibly inactivated. The enzyme also splits GTP and ITP, although to a lesser extent. 3. Mg2+-ions are essential as part of the reactive substrate, MgATP, and furthermore they activate the ATPase. Optimal conditions depend on substrate concentration. When the concentration of free Mg2+ ions exceeds about 0.1 mM, competitive inhibition occurs. 4. In the range of pH 5.6-9.2 two functional groups dissociate. One, with pKb = 8.1 +/- 0.1 participated in substrate binding and another one with pKb' = 8.1 +/- 0.1 is involved in substrate splitting. 5. The experiments with group-specific inhibitors suggest that an alpha-amino group and a sulfhydryl residue are involved in substrate binding and conversion. Furthermore, imidazole, tryptophan and carboxyl residues may be important for the catalytic process.
Mol Cell Biochem 1978 Nov 30
PMID:Kinetic characterization of plasma membrane ATPase from Saccharomyces cerevisiae. 3 25

lambdapolA phages carrying the polA gene in either orientation were isolated and characterised by genetic tests and by assay of the polA gene product after infection of E. coli or induction of lysogens. Lytic infection gave consistently better amplification of DNA polymerase I than that obtained by induction of a lysogen. Optimal amplification of DNA polymerase I was not achieved from the PL promoter of cro-phages, but some advantages accrued when the polA gene was oriented for transcription from the PL promoter of a cro+ phage. lambdapolA phages in which the polA allele was from E. coli strain C600 provided better amplification than phages with the polA allele from E. coli ED8659. Induction of a lambdapolA1 cI857 Qam Sam prophage gave levels of DNA polymerase I approaching 100 times that found in the non-lysogenic Pol+ host. Genetics studies with the lambdapolA phages confirmed the previously postulated orientation of the polA gene within the E. coli genome.
Mol Gen Genet 1979 Aug
PMID:Characterization of lambdapolA transducing phages; effective expression of the E. coli polA gene. 15 99

Protein synthesis has been studied in a cell-free system from chick embryo, in the presence of homologous RNA isolated from free and endoplasmic reticulum-bound polyribosomes. The two RNA fractions showed equal activities in total protein synthesis. However, while the RNA from bound polyribosomes mainly supported synthesis of high molecular weight, TCA-insoluble polypeptides, the RNA from free polyribosomes was more active in the synthesis of low molecular weight, TCA-soluble polypeptides. Optimal conditions for translation of the two RNA's under study were different when studied in a cell-free system with reduced content of endogenous matrix. Collagen synthesized in the system was identified by collagenase digestion. Collagen synthesis was demonstrated only in the presence of RNA from endoplasmic reticulum-bound polyribosomes, and represented 16-19% of total protein synthesis.
Mol Biol 1975 Jan
PMID:Protein biosynthesis in a homologous, cell-free system in the presence of chick embryo RNA isolated from free and membrane-bound polyribosomes. 16 98

Prostaglandins (PGA1, PGE2, PGF2 alpha) were found to increase cholesterol side-chain clevage activity in isolated bovine adrenal cortex mitochondria, provided calcium was present in the incubation medium. Optimal stimulation was observed at low PG concentrations (10-7 to 10-9 M), with malate or malate-NADPH supported side-chain cleavage. Under the same conditions, two endoperoxide analogs and several fatty acids were ineffective. The PG action was not observed with a mitochondrial acetone powder preparation. These observations suggest that primary PG may act by interfering with calcium distribution at the mitochondrial level, leading to the activation of cholesterol side-chain cleavage. Thus, an intracellular action of endogenous PG may be considered in the regulation of adrenal cortex steroidogenic functions.
Mol Cell Endocrinol 1977 Jun
PMID:Effect of prostaglandins on steroidogenesis by bovine adrenal cortex mitochondria. 40 12

The mutant tmpl--10ts which confers thermosensitive auxotrophy for thymidylate is employed for the selection of 5'-dTMP uptaking mutants. At the nonpermissive temperature yeast cells phenotypically wild type for thymidylate uptake can grow for only 3 to 4 generations in the presence of 10(-2) M 5'-dTMP. Thymidylate utilizing mutants (tum mutants) were isolated which can grow in the presence of 12 to 24 mug 5'-dTMP/ml. Genetical analysis revealed one of these mutant strains to be a double mutant, tuml tum2. For normal growth haploid thymidylate auxotrophic strains require approximately 360 mug 5'-dTMP/ml when tuml and 24 mug 5'-dTMP when tum2 is present, respectively. Cells prototrophic for thymidylate (TMP) harbouring tuml tum2 will also take up 5'-dTMP and incorporate it specifically into their DNA. Thymidylate utilization in such strains is independent of functional mitochondria, as similar incorporation of labelled 5'-dTMP is found in isogenic strains with rho+, rho- and rho0 status. Optimal stimulation of the 5'-dTMP uptaking principle in haploid TMP strains is found at 4 mug5'-dTMP/ml when tuml and tum2 are present.
Mol Gen Genet 1976 Aug 19
PMID:A simple method for the isolation and characterization of thymidylate uptaking mutants in Saccharomyces cerevisiae. 78 59

The effect of progesterone was studied on the sulfate entry in glandular epithelial cells of guinea-pig endometrium subcultured in bicameral chambers on matrix-coated filters in a chemically defined medium. At post-confluency (8 days of subculture), cells were treated with 10 nM estradiol alone or in association with various concentrations of progesterone. Optimal progesterone action was at a 16 h incubation time and a 10 nM hormonal concentration. Progesterone increased in a dose-dependent fashion the sulfate uptake specifically in glandular epithelial cells, preferentially from the basal surface. Progesterone effect on the sulfate uptake occurred only in estradiol-primed epithelial cells and was inhibited by the antiprogestin steroid RU-486. The progesterone-dependent increase in sulfate uptake was inhibited by the inhibitor of anion exchange, 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS). At physiological sulfate concentrations, progesterone essentially induces a high-affinity DIDS-sensitive transport system.
Mol Cell Endocrinol 1992 Dec
PMID:Progesterone stimulates sulfate uptake in subcultured endometrial epithelial cells. 130 1

We describe a technique of in-situ hybridization using oligonucleotide probes employing the expression of immunoglobulin VH genes as a model. Optimal conditions for hybridization with the 35S-labeled oligonucleotide probes were established with monoclonal B-cell lines that express VH genes of known nucleic acid sequence. The range of sensitivity and specificity achieved with this technique is documented. Under conditions of high stringency, this method can detect the expression of highly related VH hypervariable regions.
Diagn Mol Pathol 1992 Mar
PMID:High-specificity in-situ hybridization. Methods and application. 134 54

The human prostate tumor cell line LNCaP contains an abnormal androgen receptor system with broad steroid binding specificity. Progestagens, estradiol and several antiandrogens compete with androgens for binding to the androgen receptor in the cells to a higher extent than in other androgen sensitive systems. Optimal growth of LNCaP cells is observed after addition of the synthetic androgen R1881 (0.1 nM). In addition, estrogens, progestagens and several antiandrogens do not inhibit androgen responsive growth, but have striking growth stimulatory effects and increase EGF receptor level and acid phosphatase secretion. We have found that the androgen receptor in the LNCaP cells contains a single point mutation changing the sense of codon 868 (Thr to Ala) in the ligand binding domain. Expression vectors containing the normal or mutated androgen receptor sequence were transfected into COS or HeLa cells. Androgens, progestagens, estrogens and several antiandrogens bind the mutated androgen receptor protein and activate the expression of an androgen-regulated reporter gene (GRE-tk-CAT), indicating that the mutation directly affects both binding specificity and the induction of gene expression. Interestingly, the antiandrogen casodex showed antiandrogenic properties in growth studies of LNCaP cells and did not induce reporter gene activity in Hela cells transfected with the mutant receptor. The mutated androgen receptor of LNCaP cells is therefore a useful tool in the elucidation of different levels of action of steroids and antisteroids.
J Steroid Biochem Mol Biol 1992 Mar
PMID:The androgen receptor in LNCaP cells contains a mutation in the ligand binding domain which affects steroid binding characteristics and response to antiandrogens. 156 39

MCM1 performs several functions necessary for its role in regulating cell type-specific gene expression in the yeast Saccharomyces cerevisiae: DNA binding, transcription activation, and interaction with coregulatory proteins such as alpha 1. We analyzed a set of MCM1 deletion derivatives using in vivo reporter gene assays and in vitro DNA-binding studies to determine which regions of MCM1 are important for its various activities. We also analyzed a set of LexA-MCM1 hybrids to examine the ability of different segments of MCM1 to activate transcription independent of MCM1's DNA-binding function. The first third of MCM1 [MCM1(1-96)], which includes an 80-residue segment homologous to the mammalian serum response factor, was sufficient for high-affinity DNA binding, for activation of reporter gene expression, and for interaction with alpha 1 in vitro and in vivo. However, the ability of MCM1(1-96) to activate transcription and to interact with alpha 1 was somewhat reduced compared with wild-type MCM1 [MCM1(1-286)]. Optimal interaction with alpha 1 required residues 99 to 117, in which 18 of 19 amino acids are acidic in character. Optimal transcription activation required a segment from residues 188 to 286, in which 50% of the amino acids are glutamine. Deletion of this segment from MCM1 reduced expression of reporter genes by about twofold. Moreover, LexA-MCM1 hybrids containing this segment were able to activate expression of reporter genes that rely on LexA binding sites as potential upstream activation sequences. Thus, glutamine-rich regions may contribute to the activation function of yeast transcription activators, as has been suggested for glutamine-rich mammalian proteins such as Sp1.
Mol Cell Biol 1992 Aug
PMID:The N-terminal 96 residues of MCM1, a regulator of cell type-specific genes in Saccharomyces cerevisiae, are sufficient for DNA binding, transcription activation, and interaction with alpha 1. 163 Apr 61


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