Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.7 (DNA polymerase)
 17,007 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Degeneration of muscle fibres during the early stages of Duchenne Muscular Dystrophy (DMD) is accompanied by muscle fibre regeneration where cell division and myoblast fusion to form multinucleate myotubes within the lesions appear to recapitulate the events of normal muscle development. The mechanisms that govern the expression of genes regulating differentiation of myoblasts in regenerating skeletal muscle are of great interest for the development of future therapies designed to stimulate muscle regeneration. We show here that single-stranded breaks in DNA are localised in nuclei, using an exogenously applied medium containing labelled deoxynucleotides and the Klenow fragment of DNA polymerase I. The nuclei of a sub-population of cells lying in the inflammatory infiltrate of lesions in the skeletal muscle of the muscular dystrophic mouse (mdx), a genetic homologue of DMD, were labelled in this fashion. By contrast, labelled cells were completely absent from the muscles of normal non-myopathic animals (C57BL/10) and non-lesioned areas of mdx muscles. Cells expressing the muscle-specific regulatory gene, myogenin, were also found within mononucleate cells and myotubes within similar mdx muscle lesions. While we cannot yet say that the cells labelled by the DNA polymerase reaction are in fact differentiating, they were found only in significant numbers within mdx muscle lesions where new muscle fibres appear, providing strong circumstantial evidence that they are intimately associated with the regenerative process. Using a range of nucleases and different DNA polymerases, we show that the DNA polymerase-labelling reaction observed was DNA-dependent and most probably due to infilling of naturally occurring single-stranded gaps in DNA. Since the regenerative process in human Duchenne Muscular Dystrophy is apparently less effective than that seen in mdx mice, continued study of single-stranded DNA breaks may help to elucidate further the mechanisms controlling the expression of genes that characterise the myogenic process during skeletal muscle regeneration. Such findings might be applied in the development of future therapies designed to stimulate muscle regeneration in human dystrophies.
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PMID:In situ localisation of single-stranded DNA breaks in nuclei of a subpopulation of cells within regenerating skeletal muscle of the dystrophic mdx mouse. 132 49

In genomic diagnosis the ensemble of techniques has been recently expanded by the powerful method of the polymerase chain reaction (PCR). Using pairs of synthetic oligonucleotides for priming of synthesis and a thermoresistant DNA polymerase a millionfold amplification of target DNA sequences from patients provides DNA fragments for following investigations such as electrophoresis. The paper presents some examples of PCR application for diagnosis in cystic fibrosis and Duchenne muscular dystrophy.
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PMID:[The polymerase chain reaction PCR and its use in genetic diagnosis]. 192 Nov 62

The polymerase chain reaction is a new powerful method for in vitro cloning of specific regions of DNA. The use of the heat-stable DNA polymerase made the reaction amenable to automation. This method greatly facilitates the detection of mutations which are responsible for Duchenne muscular dystrophy, via DNA amplification of multiple deletions prone exons from the DMD gene.
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PMID:[Detection of deletions by the amplification of exons (multiplex PCR) in Duchenne muscular dystrophy]. 262 28