Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.30.1 (S1 nuclease)
 3,660 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Casein kinase II purified from nuclei of Xenopus laevis oocytes is inhibited by several specific nucleic acids. This kinase, the main phosphorylating activity of the oocyte nucleus, is markedly inhibited by poly U at 10 micrograms/ml, and this polymer is a competitive inhibitor of the phosphorylation of the substrate casein (Kiapp 80 nM). M 13 phage ssDNA and unfractionated yeast tRNA also inhibit between 50 and 200 micrograms/ml. Poly C, poly A, poly AG, dsDNA and Escherichia coli rRNA do not alter activity significantly at similar concentrations. Inhibitions are reversed by RNase (poly U, tRNA) or S1 nuclease (ssDNA). Oocyte casein kinase I or rabbit cAMP-dependent protein kinase are not inhibited by poly U at 200 micrograms/ml. The sensitivity of the casein kinase II to these inhibitors suggests a regulatory role for nucleic acids in nuclear phosphorylation reactions.
 ...
PMID:Nucleic acids can regulate the activity of casein kinase II. 279 84

The complete nucleotide sequence of the Escherichia coli ung gene is described. Transcription initiation and termination sites were determined by S1 nuclease and RNase mapping. The common prokaryotic -35, -10, and the ribosome binding site sequences are represented by TGTTCTGTA, TAAGCTA, and AGGAGAG at their respective locations. A putative hairpin transcription terminator structure is present at the major transcription terminator sites. The open reading frame of the ung gene codes for a protein of 229 amino acids (25,664 daltons). The molecular weight, amino acid composition, and the N-terminal amino acid sequence of the uracil DNA glycosylase purified from E. coli cells match with the open reading frame of the ung gene. The protein sequence analysis shows that the N-terminal methionine is cleaved off in the mature protein. The in vitro transcription coupled translation of the ung gene directs the synthesis of a protein which comigrates with uracil DNA glycosylase. Also, the CNBr cleavage of the protein synthesized in vitro confirms the positions of the methionines deduced from the DNA sequence. The levels of ung gene expression remain constant up to the early stationary phase, but decline in the late stationary phase of the E. coli culture. The E. coli gene showed a strong sequence homology to Shigella, a weak sequence homology to Salmonella and Citrobacter, and a very weak sequence homology to Proteus genes. No sequence homologies were seen for Pseudomonas, Clostridium, Micrococcus, and several eukaryotic genomes.
 ...
PMID:Sequence analysis, expression, and conservation of Escherichia coli uracil DNA glycosylase and its gene (ung). 283 97

We have isolated and sequenced a full-length cDNA clone encoding rat glyceraldehyde-3-phosphate-dehydrogenase (GAPDH, E.C.1.2.1.12). The entire mRNA is 1269 nucleotides long exclusive of poly(A) and contains respectively 71 and 196 bases of 5' and 3' non-coding regions. Primer extension as well as S1 nuclease protection experiments clearly established that a single (or at least a highly prominent) GAPDH mRNA species is expressed in all rat tissues examined. This sequence allowed the determination of the hitherto unknown primary structure of rat GAPDH which is 333 aminoacids long. Comparison between GAPDH sequences from rat, man and chicken revealed a high degree of sequence conservation at both nucleotide and protein levels.
 ...
PMID:Various rat adult tissues express only one major mRNA species from the glyceraldehyde-3-phosphate-dehydrogenase multigenic family. 298 24

Recent studies have documented the presence of a complete renin-angiotensin system in the proximal tubule of the kidney: however, little is known about the regulation of renin in this proximal tubular system. Therefore, we performed the present studies to learn whether the behavior of the renin system in cultured proximal tubule is similar to that of the juxtaglomerular renin system. Basal renin secretion from rabbit proximal tubular cells in primary culture was low and not affected by isoproterenol (10(-5) mol/L), diltiazem (10(-5) mol/L), or a zero-calcium bath (O nmol/L). Only the calcium ionophore A23187 (10(-4) mol/L) significantly reduced renin secretion in these cells (from 2.44 +/- 0.37 to 1.14 +/- O.08 ng angiotensin I/mg protein per hour, P<.05). When the proximal tubular cells were lysed so the effects of the test agents on intracellular renin content could be assessed, isoproterenol caused a significant twofold (107 percent) increase (from 2.02 +/- 0.56 to 4.18 +/- 0.81 ng angiotensin I/mg protein per hour, P<.05), whereas diltiazem, A23187, and zero- and high-calcium baths did not produce a significant change. The effects of these agents on renin mRNA were examined in rabbit and rat proximal tubular cells in primary culture with the use of an S1 nuclease protection assay. Densitometry analysis of renin mRNA and either GAPDH mRNA (rat) or alpha-actin (rabbit) showed no significant alterations in renin mRNA abundance. In summary, these results confirm the presence of renin mRNA in cultured proximal tubular cells and suggest that a low-level, constitutive secretion of renin occurs in this system that is decreased by A23187. Moreover, the results also suggest that proximal tubular renin is regulated, albeit differently from the juxtaglomerular renin system. Finally, short-term increments in proximal tubular renin occur without a change in renin mRNA.
 ...
PMID:Renin regulation in cultured proximal tubular cells. 864 45

Pathogenic processes underlying the localized reduction in neuronal number in cerebral cortex in human alcoholics have been reported to be associated with selective variations in the parameters of GABA(A) receptor site binding. Since the properties of the receptor complex depend on its isoform composition, we studied how the expression of GABA(A) receptor subunit isoform genes varied with alcoholism. Cerebral cortex tissue was obtained at autopsy from chronic human alcoholics (average ethanol intake > 80 g/day for most of their adult lives; n = 17) and matched controls (< 20 g/day ethanol; n = 15). Eight of the alcoholics and five of the controls had pathologically confirmed cirrhosis of the liver. Expression of alpha1, alpha2, alpha3, alpha5, beta1, beta3, and gamma2 GABA(A) mRNA was assessed by S1 nuclease protection assays. After phosphorimager quantitation and normalization to GAPDH mRNA and 18S rRNA, none of the mRNA species showed significantly different expression in uncomplicated alcoholics. Analysis of differences in the patterns of expression of the various subunits showed the alpha1 signal was strongest in combined cirrhotic motor cortex while the alpha3 and beta3 values were greatest in combined cirrhotic frontal cortex. It appears that only major differences in mRNA expression may be detected by this technique in human brain.
 ...
PMID:Expression of GABA(A) receptor isoform genes in the cerebral cortex of cirrhotic and alcoholic cases assessed by S1 nuclease protection assays. 959 62