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)

The enzyme 5-aminolevulinate synthase (ALA-S) catalyzes the first step in heme biosynthesis. In this study, the mouse erythroid gene has been cloned and analyzed in order to investigate the regulation of ALA-S expression during erythroid differentiation. The gene spans approximately kbp and consists of 11 exons and 10 introns. The first exon is 37 bp, non-coding, and followed by a 6kb intron. The mRNA capsite was mapped by primer extension and defines a promoter that contains no apparent TATA element. S1 nuclease analysis detects the presence at low levels of a 45 bp-deleted form of the ALA-S mRNA created by the use of an alternative splice site at the intron 2/exon 3 junction. Five DNAse I hypersensitive sites were detected in chromatin from uninduced and induced MEL cells. One site is at the promoter; the others are in the body of the gene. No significant differences were observed in the patterns or intensity of the hypersensitive sites in the uninduced and induced MEL cells, however, no sites in ALA-S were observed in NIH 3T3 cells or in deproteinized DNA. Thus, these sites are specific for erythroid chromatin but appear to be established at an earlier stage of differentiation than represented by the uninduced MEL cell.
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PMID:Structure of a mouse erythroid 5-aminolevulinate synthase gene and mapping of erythroid-specific DNAse I hypersensitive sites. 278 Mar 18

We introduced into MEL cells rabbit beta-globin gene deletion mutants and two sets of hybrid genes constructed from the inducible human beta-globin gene and noninducible human gamma-globin gene or the murine H-2Kbm1 class I MHC gene. S1 nuclease analysis of gene transcripts before and after MEL differentiation showed that induction of the rabbit beta-globin gene did not require more than 58 bp of DNA 5' to the transcription initiation site. Hybrid genes were constructed with human beta-globin DNA sequences from either 5' or 3' of the translation initiation site linked to the complementary parts of the gamma or H2Kbm1 genes. Both types of constructs were inducible during MEL differentiation. The relative rates of transcription of the 5' gamma-3' beta and 5'H2-3' beta hybrid genes show that induction of the hybrid gene transcripts results at least in part from transcriptional activation of the genes. We suggest that DNA sequences that regulate beta-globin gene transcription during MEL differentiation are located both 5' and 3' to the translation initiation site.
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PMID:DNA sequences required for regulated expression of beta-globin genes in murine erythroleukemia cells. 608 69