caa a22 4500 477089828 CHVBK 20180405111513.0 cr unu---uuuuu 170330e19960601xx s 000 0 eng 10.1007/BF02263676 doi (NATIONALLICENCE)springer-10.1007/BF02263676 Cytological evidence for 5-azacytidine-induced demethylation of the heterochromatic regions of human chromosomes [Elektronische Daten] [A. de Capoa, F. Menendez, I. Poggesi, P. Giancotti, C. Grappelli, M. Marotta, M. Di Leandro, C. Reynaud, A. Niveleau] This work was aimed at studying the effects of the demethylating agent 5-azacytidine (5-azaC) on the constitutive heterochromatin of human chromosomes at the cytological level. Metaphase preparations from peripheral blood lymphocyte and lymphoblastoid cultures obtained by standard methods were treated with the agent. Labelling of the heterochromatic regions was achieved by the indirect immunostaining method using anti-5-methylcytosine (5MeC) monoclonal antibodies and peroxidase-tagged second antibodies. 4-Chloro-1-naphthol (4C1N) was used as the substrate. The rate of methylation of individual chromosomes or chromosome groups was measured as the frequency of binding of anti-5MeC antibodies to specific chromosome regions. The following results were obtained: (i) in control cultures high intra- and interindividual variability in the binding frequencies of anti-5MeC antibodies to the short arm region of the acrocentrics was observed; (ii) 5-azaC consistently affects the methylation status of the constitutive heterochromatin; (iii) preferential demethylation occurs in the heterochromatic regions of specific chromosomes; (iv) under our experimental conditions the demethylating effect of 5-azaC appears not to be related to the well-known uncoiling effect of this drug. Rapid Science Publishers, 1996 anti-5-methylcytosine antibody nationallicence 5-azacytidine nationallicence human chromosome nationallicence methylation nationallicence de Capoa A. Department of Genetics and Molecular Biology, University of Rome ‘La Sapienza', Rome, Italy aut Menendez F. Department of Genetics and Molecular Biology, University of Rome ‘La Sapienza', Rome, Italy aut Poggesi I. Department of Genetics and Molecular Biology, University of Rome ‘La Sapienza', Rome, Italy aut Giancotti P. Department of Genetics and Molecular Biology, University of Rome ‘La Sapienza', Rome, Italy aut Grappelli C. Department of Genetics and Molecular Biology, University of Rome ‘La Sapienza', Rome, Italy aut Marotta M. Department of Genetics and Molecular Biology, University of Rome ‘La Sapienza', Rome, Italy aut Di Leandro M. Department of Genetics and Molecular Biology, University of Rome ‘La Sapienza', Rome, Italy aut Reynaud C. CNRS URA 1459 Institut Pasteur, Lyon, France aut Niveleau A. CNRS URA 1459 Institut Pasteur, Lyon, France aut Chromosome Research Kluwer Academic Publishers 4/4(1996-06-01), 271-276 0967-3849 4:4<271 1996 4 10577 https://doi.org/10.1007/BF02263676 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02263676 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- de Capoa A. Department of Genetics and Molecular Biology, University of Rome ‘La Sapienza', Rome, Italy aut NATIONALLICENCE 700 1- Menendez F. Department of Genetics and Molecular Biology, University of Rome ‘La Sapienza', Rome, Italy aut NATIONALLICENCE 700 1- Poggesi I. Department of Genetics and Molecular Biology, University of Rome ‘La Sapienza', Rome, Italy aut NATIONALLICENCE 700 1- Giancotti P. Department of Genetics and Molecular Biology, University of Rome ‘La Sapienza', Rome, Italy aut NATIONALLICENCE 700 1- Grappelli C. Department of Genetics and Molecular Biology, University of Rome ‘La Sapienza', Rome, Italy aut NATIONALLICENCE 700 1- Marotta M. Department of Genetics and Molecular Biology, University of Rome ‘La Sapienza', Rome, Italy aut NATIONALLICENCE 700 1- Di Leandro M. Department of Genetics and Molecular Biology, University of Rome ‘La Sapienza', Rome, Italy aut NATIONALLICENCE 700 1- Reynaud C. CNRS URA 1459 Institut Pasteur, Lyon, France aut NATIONALLICENCE 700 1- Niveleau A. CNRS URA 1459 Institut Pasteur, Lyon, France aut NATIONALLICENCE 773 0- Chromosome Research Kluwer Academic Publishers 4/4(1996-06-01), 271-276 0967-3849 4:4<271 1996 4 10577 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer