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)

Antibodies against purine nucleotides were obtained from rabbits immunized with conjugates of bovine serum albumine with AMP or GMP. The antibodies purified by affinity chromatography on nucleoside monophosphate-human serum albumine-Sepharose columns inhibited RNA synthesis on native T4 phage DNA by E. coli RNA polymerase. The inhibition of transcription was due mainly to inhibition of the initiation stage of RNA synthesis.
Mol Biol (Mosk)
PMID:[Inhibition of RNA synthesis in vitro by antibodies against mononucleotides]. 9 37

Wild type and mutant strains of Neurospora crassa excrete hypoxanthine, xanthine, and uric acid, but not adenine or inosine, when exogenous adenine is added to growing cultures. No detectable excretion occurs in the absence of adenine. The de novo pathway of purine biosynthesis was found to influence the excretion, in that a metabolic block immediately prior to IMP significantly decreased the excretion, while a metabolic block immediately after IMP significantly increased the excretion over that of wild type. The purine catabolic pathway, which is sensitive to ammonia regulation, was found to be a key determinant in the amount and type of excretion. Recently, it was suggested that hypoxanthine accumulation is the result of a mechanism to regulate the adenylate pool size (Leung and Schramm, 1978). In this report, the possibility that hypoxanthine excretion controls adenylate and guanylate pool sizes is discussed and the role of the purine nucleotide cycle in hypoxanthine excretion is examined.
Mol Gen Genet 1979 May 23
PMID:Role of purine base excretion in regulation of purine pools. 15 18

The incorporation of [2H]thymidine into nuclear DNA was investigated in cultured Sertoli cells prepared from testes of 20-day-old rats. Addition of follicle-stimulating hormone (FSH) or dibutyryl cyclic, 3',5'-adenosine monophosphate (DBCAMP) to the culture medium greatly increased incorporation, expressed either as total amounts of [3H]thymidine incorporated per mug DNA or as the percentage of Sertoli cells with labeled nuclear DNA. No stimulation was observed in cells cultured in the presence of testosterone, insulin or cyclic 3',5'-GMP (cGMP). Light and electron microscopic autoradiographic analysis was employed to establish the identity of Sertoli cells having labeled nuclear DNA. Contaminating spermatogonia, which also took up labeled [3H]thymidine, were excluded from cell counts. In addition, Sertoli cells prepared from testes of irradiated 20-day-old germinal cell depleted rats were also observed to incorporate more [3H]thymidine into nuclear DNA when cultured in a chemically defined medium in the presence of FSH. DNA synthesis was abolished by prior treatment of cells with cytosine arabinoside. In separate experiments, the incorporation of [3H]thymidine into DNA of peritubular myoid cells was shown to be independent of FSH or dbcAMP.
Mol Cell Endocrinol 1976 Feb
PMID:FSH stimulation of DNA synthesis in Sertoli cells in culture. 17 64

Stopped-flow spectrophotometric studies of the reductive amination of L-ketoglutarate by L-glutamate dehydrogenase showed a biphase time course, which consisted of a rapid first phase lasting 60-100 msec and a slow final phase in which the rate of coenzyme oxidation increased until the coenzyme was depleted. The effects of 3',5'-cyclic adenosine monophosphate (cAMP) and 3',5'-cyclic guanosine monophosphate (cGMP) on the time course of both phases were established. The results showed that in the concentration ranges used the cyclic nucleotides accelerate the catalytic reaction. The effect of cAMP was more pronounced as compared to cGMP. In all cases this influence was most clearly expressed in the first phase. Using an Arrhenius plot the activation parameters were calculated. The experiments with cAMP and cGMP at different molar ratios showed that a specific cAMP binding may occur.
Mol Biol Rep 1978 Feb 28
PMID:Studies on the kinetic effects of cyclic nucleotides dependent glutamate dehydrogenase. 20 75

The effect of m7GMP release from m7GMP-containing mRNA cap sequence m7GpppG by the embryonic chick lens m7GpppN-pyrophosphatase activity on the synthesis of lens proteins was examined in a newly developed homologous translation system derived from 15-day embryonic chick lenses. The synthesis of total lens polypeptides and delta-crystallin polypeptides, the major translation product, was inhibited 84% and 88%, respectively, by 0.5 mM m7GpppG; m7GMP (0.5 mM) inhibited total synthesis by 63% but was 33% less inhibitory toward delta-crystallin synthesis; GpppG and GMP were not inhibitors, m7GpppG inhibited met-tRNAfmet incorporation into 80S initiation complexes.
Mol Biol Rep 1979 Feb 15
PMID:Differential synthesis of lens proteins in the presence of m7G(5')pppG and cleavage product m7GMP in an embryonic chick lens cell lysate. 22 May 21

In a previous report we have shown that insulin increases the phosphorylation of an endogenous protein of mol. wt. 16 000 daltons in sarcolemma membranes. In the present work we have demonstrated that phosphorylations of exogenous histones by the sarcolemma membranes are also increased by insulin. These results indicate that insulin activates a cyclic-AMP-independent protein kinase in sarcolemma membranes. The stimulatory effect of insulin on protein phosphorylations is increased by GTP and its analogue GMP-P(NH)P. The insulin effect was increased 3--4-fold by micromolar concentrations of GTP. The effect by the analogue GMP-P(NH)P was somewhat less. In the absence of insulin guanosine nucleotides had no effect on phosphorylation of the proteins. The results suggest that GTP is a modulator in the activation of a sarcolemma membrane protein kinase by insulin.
Mol Cell Endocrinol 1979 Oct
PMID:The effect of insulin and guanosine nucleotides on protein phosphorylations by sarcolemma membranes from skeletal muscle. 22 62

A large number of hormones and neurotransmitters activate adenylyl cyclase [ATP, pyrophosphate lyase (cyclizing; EC 4.6.1.1.)] catalyzing the formation of cAMP and PPi from ATP in the presence of Mg2+. The cAMP formed is in turn responsible for eliciting the physiological responses of these hormones and neurotransmitters. In addition to hormones and neurotransmitters, fluoride ion, cholera toxin and guanyl nucleotides (GTP and GTP analogs such as GTP gamma S and GMP-P(NH)P) also stimulate adenylyl cyclase activity (Perkins, 1974; Birnbaumer, 1977; Gill, 1977). It has become evident that hormonally-responsive adenylyl cyclase is a multi-component system consisting of at least 3 physically distinct units. The first is the hormone receptor containing a specific site for a given hormone. The second is the catalytic moiety (C component) of adenylyl cyclase bearing the site responsible for catalysis of the cyclizing reaction. The third is the guanyl nucleotide regulatory subunit (G component) which binds guanyl nucleotide. Recently, a GTPase activity has been found to be associated with the G component of adenylyl cyclase (Cassel and Selinger, 1976; Cassel et al., 1977a, b; Lambert et al., 1979). In this review we will present information on the regulation of hormonally-responsive adenylyl cyclases. This is not intended to be a comprehensive review of the literature. Rather, it represents our views on the current status of the regulation of cAMP formation.
Mol Cell Endocrinol 1979 Dec
PMID:Guanyl nucleotide regulation of hormonally-responsive adenylyl cyclases. 23 Jan 2

Columns containing ribosomes translating poly(U) covalently bound with cellulose (solid-phase translating system) were used to study translocation in ribosomes. It is shown that the passing of elongation factor G (EF-G) with the non-cleavable analog of GTP (GMP-PCP) through a column containing pre-translocated ribosomes results in the increase of competence for puromycin (i. e. to the transition of pre-translocated peptidyl-tRNA into the post-translocated state) just as in the case of the passing of EF-G with GTP. On the other hand, it is shown that the passing of EF-G with GMP-PCP through a column with pre-translocated ribosomes makes them capable of binding the next aminoacyl-tRNA (i. e. leads to the vacation of the ribosomal A-site). Thus, by means of the two independent tests it is shown that EF-G-promoted translocation in the ribosome can proceed without GTP hydrolysis. On the basis of the data obtained, a controlled step-wise elongation of polypeptide with the participation of EF-G without GTP cleavage has been carried out in the solid-phase column system of translation.
Mol Biol (Mosk)
PMID:[Translocation in ribosomes induced by elongation factor G without cleavage of GTP. Study using a solid phase translation system in columns]. 25 70

The two species of Elongation Factor Tu coded for by the tufA and tufB genes were synthesized in UV-irradiated E coli infected by transducing phages bearing the separate genes. Both proteins interact similarly with EFTs, GDP, and phe-tRNA. Although the phe-tRNA.EFTu.GMP.PNP complex containing the tufA gene product binds somewhat more tightly to ribosomes, both proteins promote the complete process of binding phe tRNA to ribosomes at similar rates.
Mol Gen Genet 1978 Feb 07
PMID:A comparison of the activities of the products of the two genes for elongation factor Tu. 34 85

ATP gamma-(p-azidoanilidate) (1) and ATP gamma-(p-azidobenzyl)-methylanilidate (2) were shown to be competitive inhibitors for ATP and amino acid in tRNA aminoacylation catalyzed by E. coli MRE-600 phenylalanyl-tRNA synthetase (E.C.6.1.1.20). Low concentration (10(-5)--10(-6) M) of either ATP, gamma-anilidate or GMP stimulates the aminoacylation of tRNA suggesting their interaction with some nucleotide binding sites of the enzyme other than catalytic ones. Covalent photobinding of (1) to the enzyme does not inhibit aminoacylation, nor does it prevent nucleotides from activating the enzyme. UV-irradiation of the synthetase in the presence of (2) results in complete inactivation of the enzyme which can be prevented by phenylalanine or phenylalanine-ATP to save 50% of the enzyme activity but not ATP and tRNA. The photobinding of (2) to the enzyme in the presence of phenylalanine and ATP removes the activation of the enzyme by nucleotides suggesting that both the catalytic and effector sites of the synthetase are blocked in the same manner by compound (2).
Mol Biol (Mosk)
PMID:[Influence of the structure of photoreactive ATP analogs on the affinity modification of phenylalanyl-tRNA synsthetase. Modification of the enzyme at two types of nucleotide sites]. 38 88


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