Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.49 (reverse transcriptase)
 31,746 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The iduronate-2-sulfatase (IDS) is a lysosomal enzyme that acts on sulphate groups on C-2 positions of the iduronic acid residues of the mucopolysaccharides heparan sulphate and dermatan sulphate. Recently, we described in mouse two IDS mRNAs: the first or canonic (MTA16), highly homologous to the human counterpart, the second or novel (MTA13), completely divergent from the canonic in the 3' region. In this study, by reverse transcriptase polymerase chain reaction (RT-PCR) we analyzed the expression of the two mRNA transcripts for the IDS gene in murine tissues, in various human cell-lines and in cells from some Hunter patients.
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PMID:Expression of the two iduronate-2-sulfatase cDNAs. 766 35

An investigation was initiated to explore previously published results indicating that approximately 80 bp of the 5'-end of the iduronate sulfatase (IDS) cDNA sequence (Accession No L07291) are 100% homologous with the 3'-UTR of isoform I of the sodium hydrogen exchanger (Acc. No. U51112). 5'-RACE carried out on IDS mRNA demonstrated the apparent homology to be a cloning artifact. A sequence comparison of the IDS 5'-RACE product with a mouse BAC clone covering the region, and with various IDS ESTs, suggested that the region is highly susceptible to cloning artifacts, a common one of which is template switching by reverse transcriptase. The nucleotide sequence flanking the translation start site is unusual in containing two inverted repeats composed of the complementary trinucleotide microsatellites, (GCG)9 and (CGC)6. These likely form a highly stable stem of 20-21 nt, through which reverse transcription is compromised. Such a stem could be involved in the regulation of IDS expression by directly affecting translation, message turnover, or serving as a substrate for siRNA production. Though such mRNA features are relatively rare, they may be more abundant but overlooked due to difficulties in their reverse transcription.
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PMID:Inverted Gcg/CGC trinucleotide microsatellites in the 5'-region of Mus IDS mRNA: recurrent induction of aberrant reverse transcripts. 1529 86

Mutations in the gene encoding the enzyme iduronate-2-sulfatase (IDS) were reported as the cause of the X-linked recessive lysosomal disease, mucopolysaccharidosis II (MPS II). Amongst the different mutations, it emerges that nearly 10% are nucleotide substitutions causing splicing mutations. We now report the molecular characterisation of three MPS II patients with multiple aberrant transcripts due to three different point mutations. The c.418+1G>C that occurred in the invariant splice-site motif, produced only aberrantly spliced transcripts. Whilst the mutations affecting variant motifs (c.419G>T) or coding regions (c.245C>T) led to aberrantly spliced transcripts in addition to correctly spliced transcripts with the respective predicted missense mutation, p.G140V or p.A82V. A combination of experimental tests and computational approaches were used to understand the molecular basis underlying the altered transcription patterns. In addition, by using real-time reverse transcriptase polymerase chain reaction, the reduction of mRNA amount in two patients observed was likely due to nonsense-mediated mRNA decay pathway. Overall, our results further emphasised the importance of cloning and sequencing independent transcripts to reveal less abundant, aberrant products, which often could not be detected by direct sequencing. Moreover, the different splicing patterns observed in the three patients as a consequence of point mutations show how sensitive the balance is between constitutive and cryptic splice sites in the IDS gene. The generation of such diverse transcripts, together with their level of expression, could contribute to the profound phenotypic variability reported in MPS II.
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PMID:Multiple cryptic splice sites can be activated by IDS point mutations generating misspliced transcripts. 1669 54