Artículos de revistas
Restriction Enzyme Analysis Of Dna Methylation In "condensed" Chromatin Ha-ras-transformed Nih 3t3 Cells
Analytical Cellular Pathology. , v. 20, n. 4, p. 163 - 171, 2000.
Increased amounts of chromatin condensation (i.e., localized areas of high DNA density, or chromatin higher order packing state) have been described in NIH 3T3 cells transformed with the Ha-ras oncogene. The structural basis for this oncogene-mediated alteration in nuclear organization is unknown. Since DNA methylation is likely to be involved in regulating the nucleosomal level of DNA packaging, we studied the role of DNA methylation in higher-order chromatin organization induced by Ha-ras. CpG-methylated DNA content was estimated in "condensed" chromatin of Ha-ras-transformed NIH 3T3 cell lines which differ in ras expression and ras-induced metastatic ability but present approximately the same values of "condensed" chromatin areas. The question posed was that if DNA methylation were involved with the chromatin higher-order organization induced by Ha-ras in these cell lines, the methylated DNA density in the "condensed" chromatin would also be the same. The DNA evaluation was performed by video image analysis in Feulgen-stained cells previously subjected to treatment with Msp I and Hpa II restriction enzymes, which distinguish between methylated and non-methylated DNA. The amount of methylated CpG sequences not digested by Hpa II in "condensed" chromatin regions was found to vary in the studied ras-transformed cell lines. DNA CpG methylation status is thus suggested not to be involved with the higher order chromatin condensation induced by ras transformation in the mentioned NIH 3T3 cell lines.204163171Antequera, F., Boyes, J., Bird, A., High levels of de novo methylation and altered chromatin structure at CpG islands in cell lines (1990) Cell, 62, pp. 503-514Balmain, A., Exploring the bowels of DNA methylation (1995) Curr. Biol., 5, pp. 1813-1816Barbisan, L.F., Russo, J., Mello, M.L.S., Nuclear and nucleolar image analysis of human breast epithelial cells transformed by benzo[a]pyrene and transfected with the c-Ha-ras oncogene (1998) Anal. Cell. Pathol., 16, pp. 193-199Baylin, S.B., Tying it all together: Epigenetics, genetics, cell cycle, and cancer (1997) Science (Washington), 277, pp. 1948-1949Bianchi, N.O., Morgan, W.F., Cleaver, J.E., Relationship of ultraviolet light-induced DNA-protein cross-linkage to chromatin structure (1985) Exptl. Cell Res., 156, pp. 405-418Chadee, D.N., Taylor, W.R., Hurta, R.A.R., Allis, C.D., Wright, J.A., Davie, J.R., Increased phosphorylation of histone H1 in mouse fibroblasts transformed with oncogenes or constitutively active mitogen-activated protein kinase kinase (1995) J. Biol. Chem., 270, pp. 20098-20105Chambers, A.F., Denhardt, G.H., Wilson, S.M., Ras-transformed N1H 3T3 cell lines selected for metastatic abitity in chick embryos have increased proportions of p21 expressing cells and are metastatic in nude mice (1990) Invasion Metastasis, 10, pp. 225-240Costello, J.F., Berger, M.S., Huang, H.J.S., Cavenee, W.K., Silencing of p16/CDKN2 expression in human gliomas by methylation and chromatin condensation (1996) Cancer Res., 56, pp. 2405-2410Fischer, A.H., Chadee, D.N., Wright, J.A., Gansler, T.S., Davie, J.R., Ras-associated nuclear structural change appears functionally significant and independent of the mitotic signaling pathway (1998) J. Cell Biochem., 70, pp. 130-140Gosalvez, J., López-Fernández, C., Fernández, J.L., Goyanes, J., Buño, I., Digital image analysis of chromatin fibre phenotype after "in situ" digestion with restriction endonucleases (1995) Cell Biol. Int., 19, pp. 827-832Hill, S.A., Wilson, S., Chambers, A.F., Clonal heterogeneity, experimental metastatic ability, and p21 expression in H-ras-transformed NIH 3T3 cells (1988) J. Natl. Cancer Inst., 80, pp. 484-490Jones, P.A., Buckley, J.D., The role of DNA methylation in cancer (1990) Adv. Cancer Res., 54, pp. 1-23Laitinen, J., Sistonen, L., Alitalo, K., Hölttä, E., c-Ha-rasVal12 oncogene-transformed NIH-3T3 fibroblasts display more decondensed nucleosomal organization than normal fibroblasts (1990) J. Cell Biol., 111, pp. 9-17Laitinen, J., Saris, P., Holtta, E., DNA methylation is not involved in the structural alterations of ornithine decarboxylase or total chromatin of c-Ha-ras(Val-12) oncogene-transformed N1H-3T3 fibroblasts (1995) J. Cell Biochem., 57, pp. 670-679Ludérus, M.E.E., Van Driel, R., (1997) Nuclear Organization, Chromatin Structure, and Gene Expression, pp. 99-115. , R. van Driel and A.P. Otte, eds, Oxford Univ. Press, OxfordMacLeod, A.R., Rouleau, J., Szyf, M., Regulation of DNA methylation by the ras signaling pathway (1995) J. Biol. Chem., 270, pp. 11327-11337Manuelidis, L., A view of interphase chromosomes (1990) Science (Washington), 250, pp. 1533-1540Mello, M.L.S., Cytochemistry of DNA, RNA and nuclear proteins (1997) Braz. J. Genet., 20, pp. 257-264Mello, M.L.S., Chambers, A.F., Image analysis of Feulgenstained transformed NIH 3T3 cells differing in p21 expression and ras-induced metastatic ability (1994) Analyt. Quant. Cytol. Histol., 16, pp. 113-123Mello, M.L.S., Russo, J., Image analysis of Feulgen-stained c-H-ras-transformed NIH/3T3 cells (1990) Biochem. Cell Biol., 68, pp. 1026-1031Mello, M.L.S., Vidal, B.C., Planding, W., Schenck, U., Image analysis: Video system adequacy for the assortment of nuclear phenotypes based on chromatin texture evaluation (1994) Acta Histochem. Cytochem., 27, pp. 23-31Mello, M.L.S., Contente, S., Vidal, B.C., Planding, W., Schenck, U., Modulation of ras transformation affecting chromatin supraorganization as assessed by image analysis (1995) Exp. Cell Res., 220, pp. 374-382Mezzanotte, R., Bianchi, U., Vanni, R., Ferruci, L., Chromatin organization and restriction endonuclease activity on human metaphase chromosomes (1983) Cytogenet. Cell Genet., 36, pp. 562-566Nelson, M., McClelland, M., Site-specific methylation effect on DNA modification methyltransferases and restriction endonucleases (1991) Nucleic Acids Res., 19, pp. 2045-2071Samuel, S.K., Minish, T.M., Davie, J.R., Altered nuclear matrix protein profiles in oncogene-transformed mouse fibroblasts exhibiting high metastatic potential (1997) Cancer Res., 57, pp. 147-151Schedl, P., Grosveld, F., Domains and boundaries (1995), pp. 172-196. , Chromatin Structure and Gene Expression, S.C.R. Elgin, ed., IRL Press, OxfordSchmutte, C., Yang, A.S., Nguyen, T.T., Beart, B.W., Jones, P.A., Mechanisms for the involvement of DNA methylation in colon carcinogenesis (1996) Cancer Res., 56, pp. 2375-2381Sentis, C., Santos, J., Fernandez-Piqueras, J., Breaking up the chromosomes of Baetica ustulata by in situ treatments with restriction endonucleases (1989) Genome, 32, pp. 208-215Vidal, B.C., Russo, J., Mello, M.L.S., DNA content and chromatin texture of benzo[a]pyrene-transformed human breast epithelial cells as assessed by image analysis (1998) Exptl Cell Res., 244, pp. 77-82Wu, J., Issa, J.P., Herman, J., Bassett, D.J., Nelkin, B.D., Baylin, S.B., Expression of an exogenous eukaryotic DNA methyltransferase gene induces transformation of NIH 3T3 cells (1993) Proc. Natl. Acad. Sci. USA, 90, pp. 8891-8895