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 human adenosine deaminase cDNA has been cloned in a lambda-vector. Contained within a sequence of over 1500 nucleotides is an open reading frame of 1089 nucleotides that encodes the amino acids of ADA. The functional ADA gene contains at least six kilobases and has at least two introns. Using in vitro translation, molecular hybridization to ADA cDNA, and S1 nuclease mapping, ADA mRNA has been characterized in lymphoblast lines from seven different ADA-deficient children. All of the lines contain substantial amounts of RNA, which hybridizes specifically to the ADA cDNA. Four of the cell lines contain translatable mRNAs with small defects such as single base substitutions that are not detectable by S1 mapping. Deficiency of ADA activity in these lines appears secondary to synthesis of structurally altered proteins containing simple amino acid substitutions. Three of the lines contain mRNAs with S1 nuclease detectable defects. Some or all of these defective mRNAs are postulated to result from anomalous RNA processing. In these cases the causes of the ADA deficiency may be more complex than simple amino acid substitutions in the protein and could include small insertions or deletions of amino acids as well as changes in the efficiency of translation of the mRNAs.
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PMID:Molecular biology of the adenosine deaminase gene and messenger RNA. 386 73

The structure of human adenosine deaminase mRNA from normal and mutant lymphoblasts was examined by sequence analysis of a cDNA for normal mRNA and electrophoretic analyses of DNA fragments generated by S1 endonuclease cleavage of mRNA-cDNA hybrids. The 1,533-base sequence of the cloned cDNA represents the complete mRNA sequence with the possible exception of some of the 5' untranslated region. S1 nuclease analyses of hybrids between cloned cDNA and normal adenosine deaminase mRNA confirmed that a 76-base sequence in a previously examined adenosine deaminase cDNA is an intron. S1 nuclease analyses of mRNAs from seven mutant cell lines demonstrated that four of the mutants, those in the GM-2471, GM-2756, GM-4258, and GM-2606 cells, contain small defects, such as single-base changes, that are not detectable by the S1 nuclease technique. Three of the mRNAs, those in GM-3043, GM-2294, and GM-2825A cells, do contain defects detectable with S1 nuclease. These defects differ from each other and have been mapped to specific regions of the mRNA. Some or all of these defective mRNAs are postulated to result from anomalous RNA processing.
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PMID:Structure of adenosine deaminase mRNAs from normal and adenosine deaminase-deficient human cell lines. 620 79