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

Rats and mice both express two, non-allelic, insulin genes. In the rat the ratio of the two preproinsulin mRNAs closely matches that of the mature insulin peptides. The experiments reported here demonstrate that this is not the case in the mouse. The relative amounts of the two murine proinsulin RNAs were measured by an S1 nuclease assay. The ratio of preproinsulin I mRNA to preproinsulin II mRNA was 4:1 in RNA extracted from the pancreas of mice fed ad libitum or fasted for 72 h. A similar value was found in mouse islets of Langerhans after maintenance in tissue culture for 48 h at either 2.8 or 16.7 mM glucose. The ratio of insulin I:insulin II peptides, assessed by separating the two insulins using reversed phase high-performance liquid chromatography, was approximately 1:3 in both pancreas and islets. Thus in the mouse, unlike the rat, the ratio of the two insulin peptides does not reflect that of the two preproinsulin mRNAs.
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PMID:The ratio of mouse insulin I:insulin II does not reflect that of the corresponding preproinsulin mRNAs. 151 87

Using a quantitative S1 nuclease protection assay, we demonstrated that acute or chronic infection of avian cells enhances expression of an exogenously introduced rat preproinsulin II gene by approximately equal to 50-fold. The degree of enhancement is shown to vary with the transfection technique used but is independent of the transcription control region of the transfected gene. We conclude that retroviral infection of avian cells enhances expression of transfected DNA in trans by facilitating the uptake of DNA rather than by activating the transfected promoter.
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PMID:Expression of transfected DNA in avian cells can be enhanced in trans by retroviral infection. 299 53

We have cloned and sequenced the two mouse preproinsulin genes. The deduced amino acid sequences of the mature mouse insulins are identical to the published protein sequences. However, the nucleotide sequence indicates that the mouse I C-peptide has a deletion of two amino acids compared with the mouse II C-peptide. We used an S1 nuclease assay to confirm the presence of the deletion and to measure the ratio of transcripts from gene I to transcripts from gene II. The mouse preproinsulin I gene, like the rat gene I, is missing the second intervening sequence that normally interrupts the C-peptide region in other insulin genes. Comparison of the 5' flanking sequences of the mouse and rat genes II indicates that they are homologous for at least 1000 base pairs. The preproinsulin I genes also share homology in their 5' flanking DNAs; however, their homology to the preproinsulin II genes extends for only about 500 base pairs.
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PMID:Characterization of the two nonallelic genes encoding mouse preproinsulin. 310 3

We have examined by fine mapping the S1 nuclease-hypersensitivity of the 5' flanking regions of the human beta-globin and rat preproinsulin II genes and of the SV40 origin/enhancer region. In all cases S1-hypersensitive sites are located in known or presumed promoter/regulatory regions. Though a consensus DNA sequence is not evident, all of these sites reside in predominantly homopurine-homopyrimidine stretches. The alternate (non-B) DNA structure which is revealed by the enzymatic probe is a sequence-dependent feature of a short stretch of DNA, which is retained upon transplantation into a foreign environment. The alternate structure exhibits S1-nicking patterns uniquely different from those associated with the presence of Z-DNA.
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PMID:S1-hypersensitive sites in eukaryotic promoter regions. 609 86

A novel eucaryotic vector derived from the transforming region of bovine papilloma virus was established and demonstrated to be highly effective for introducing foreign genes into animal cells. The foreign deoxyribonucleic acid (DNA) is replicated and actively transcribed as an episome, and the transcripts are translated into an authentic gene product. We have constructed a DNA hybrid molecule, BPV69T-rI1, containing the transforming region of bovine papilloma virus DNA and the rat preproinsulin gene I (rI1), and used it to transform susceptible mouse cells. DNA hybridization analysis has demonstrated the presence of multiple unintegrated copies of hybrid DNA molecules, with the bovine papilloma virus 1 DNA segment and the rI1 gene covalently linked in selected transformed cell lines. S1 nuclease analysis revealed the presence of a correctly spliced coding segment of the preproinsulin transcript similar or identical in its electrophoretic mobility to that of messenger ribonucleic acid produced in rat insulinoma cells. Significant levels of a protein immunoreactive with anti-insulin serum were detected by radioimmunoassay in the culture medium of transformed cells. Immunoprecipitation analysis in conjunction with competitive binding to bovine proinsulin established the identity of the protein as that of rat proinsulin.
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PMID:Bovine papilloma virus deoxyribonucleic acid: a novel eucaryotic cloning vector. 610 Sep 67