Methylation of the 5' flanking sequences of the ribosomal DNA in human cell lines and in a human-hamster hybrid cell line

R. Dante, M. E. Percy, A. Baldini, V. D. Markovic, D. A. Miller, M. Rocchi, A. Niveleau, O. J. Miller

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

In a human lymphoblastoid cell line (Z83) in which rDNA genes on chromosome 22 are amplified but transcribed at a low level, immunocytological studies with antibodies to 5 methylcytidine provided evidence for hypermethylation of the rDNA. The extent of methylation of the 5' flanking sequences of the ribosomal DNA was examined by comparing the size of restriction fragments obtained by digestion of genomic DNA with EcoRI and HpaII or EcoRI and MspI. Southern blots indicated hypermethylation of the 5' flanking sequences of many copies of rRNA genes in these cells, but not in a control lymphoblastoid cell line without rDNA amplification. Results obtained with a somatic hybrid human-hamster cell line, in which the rRNA genes on the single human chromosome 22 are inactive, showed that only a small fraction of the CCGG sites in the 5' flanking sequences of the transcriptionally silent rRNA genes in this hybrid were methylated. Since inactive rRNA genes can show such a minimal level of methylation, it is likely that the extreme hypermethylation of the amplified rRNA genes in Z83 occurred in association with their inactivation rather than following it.

Original languageEnglish
Pages (from-to)357-362
Number of pages6
JournalJournal of Cellular Biochemistry
Volume50
Issue number4
DOIs
Publication statusPublished - 1992

Fingerprint

Methylation
Hybrid Cells
5' Flanking Region
Ribosomal DNA
rRNA Genes
Cricetinae
Genes
Cells
Cell Line
Chromosomes, Human, Pair 22
Chromosomes
Human Chromosomes
Southern Blotting
Digestion
Amplification
Association reactions
Antibodies
DNA

Keywords

  • DNA
  • hypermethylation
  • lymphoblastoid
  • methylation
  • rDNA

ASJC Scopus subject areas

  • Biochemistry
  • Cell Biology

Cite this

Dante, R., Percy, M. E., Baldini, A., Markovic, V. D., Miller, D. A., Rocchi, M., ... Miller, O. J. (1992). Methylation of the 5' flanking sequences of the ribosomal DNA in human cell lines and in a human-hamster hybrid cell line. Journal of Cellular Biochemistry, 50(4), 357-362. https://doi.org/10.1002/jcb.240500404

Methylation of the 5' flanking sequences of the ribosomal DNA in human cell lines and in a human-hamster hybrid cell line. / Dante, R.; Percy, M. E.; Baldini, A.; Markovic, V. D.; Miller, D. A.; Rocchi, M.; Niveleau, A.; Miller, O. J.

In: Journal of Cellular Biochemistry, Vol. 50, No. 4, 1992, p. 357-362.

Research output: Contribution to journalArticle

Dante, R, Percy, ME, Baldini, A, Markovic, VD, Miller, DA, Rocchi, M, Niveleau, A & Miller, OJ 1992, 'Methylation of the 5' flanking sequences of the ribosomal DNA in human cell lines and in a human-hamster hybrid cell line', Journal of Cellular Biochemistry, vol. 50, no. 4, pp. 357-362. https://doi.org/10.1002/jcb.240500404
Dante, R. ; Percy, M. E. ; Baldini, A. ; Markovic, V. D. ; Miller, D. A. ; Rocchi, M. ; Niveleau, A. ; Miller, O. J. / Methylation of the 5' flanking sequences of the ribosomal DNA in human cell lines and in a human-hamster hybrid cell line. In: Journal of Cellular Biochemistry. 1992 ; Vol. 50, No. 4. pp. 357-362.
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