title: Characterization of the human ornithine transcarbamylase 3' untranslated regulatory region.
abstract: Mutations in the untranslated regulatory regions of genes may result in abnormal gene expression or transcriptional regulation. In this study, we characterize the ornithine transcarbamylase (OTC) mRNA isoforms of the X-linked OTC gene involved in the urea formation in the liver. Our data revealed that two major transcripts (OTC-t1 and OTC-t2) are more highly expressed than any of the other isoforms in all the tissues analyzed, though a longer transcript (OTC-t3) was also isolated and characterized from the brain sample. The OTC-t2 sequence fully matches the OTC mRNA reference sequence (NM_000531.5). All three isoforms use a canonical AAUAAA hexamer that is predicted to fold into a hairpin secondary structure which might be exposed to the cleavage and polyadenylation specificity factor. In addition, we observed that the OTC-t1 and OTC-t2 transcripts display heterogeneity at the cleavage sites in a tissue-dependent manner. Taken together, our data demonstrate that several mRNA isoforms are transcribed from the OTC gene, thereby indicating a wide degree of variability in post-transcriptional regulation.
authors: Population Genetics Group, IPATIMUP-Institute of Molecular Pathology and Immunology of the University of Porto, Porto, Portugal.
authors: Monica
authors: M
authors: Lopes-Marques
authors: Isabel
authors: I
authors: Pereira-Castro
authors: António
authors: A
authors: Amorim
authors: Luisa
authors: L
authors: Azevedo
mesh_terms: D020413:3' Untranslated Regions / Q000235:genetics*; D020029:Base Pairing; D001483:Base Sequence; D001921:Brain / Q000378:metabolism; D019295:Computational Biology; D017931:DNA Primers / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D020224:Expressed Sequence Tags; D020869:Gene Expression Profiling; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics*; D006801:Humans; D007527:Isoenzymes / Q000235:genetics; D008099:Liver / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D009954:Ornithine Carbamoyltransferase / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
chemical_list: D020413:3' Untranslated Regions; D017931:DNA Primers; D018076:DNA, Complementary; D007527:Isoenzymes; D012333:RNA, Messenger; D009954:Ornithine Carbamoyltransferase