|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | |||||
Journal of Cell Science, Vol 112, Issue 23 4397-4404, Copyright © 1999 by Company of Biologists
JOURNAL ARTICLES |
A Castilho, N Neves, M Rufini-Castiglione, W Viegas and JS Heslop-Harrison
Karyobiology Group, Dep. of Cell Biology, John Innes Centre, Colney Lane, Norwich NR4 7UH, UK.
Triticale (2n=6x=42) is a hybrid plant including rye (R) and wheat (A and B) genomes. Using genomic in situ hybridization with rye DNA as a probe, we found the chromosomes of the R genome were not intermixed with the wheat chromosomes in 85% of nuclei. After treatment of seedlings with low doses of the drug 5-azacytidine (5-AC), leading to hypomethylation of the DNA, the chromosomes became intermixed in 60% of nuclei; the next generation showed intermediate organization. These results correlate with previous data showing that expression of R-genome rRNA genes, normally suppressed, is activated by 5-AC treatment and remains partially activated in the next generation. The distribution of 5-methylcytosine (5-mC) was studied using an antibody to 5-mC. Methylation was detected along the lengths of all chromosomes; there were some chromosome regions with enhanced and reduced methylation, but these were not located at consistent positions, nor were there differences between R and wheat genome chromosomes. After 5-AC treatment, lower levels of methylation were detected. After 5-AC treatment, in situ hybridization with rye genomic DNA sometimes showed micronuclei of rye origin and multiple translocations between wheat and rye chromosomes. Genomic DNA was analysed using methylation-sensitive restriction enzymes and, as probes, two rDNA sequences, two tandemly organised DNA sequences from rye (pSc200 and pSc250), and copia and the gypsy group retrotransposon fragments from rye and wheat. DNA extracted immediately after 5-AC treatment was cut more by methylation-sensitive restriction enzymes than DNA from untreated seedlings. Each probe gave a characteristic restriction fragment pattern, but rye- and wheat-origin probes behaved similarly, indicating that hypomethylation was induced in both genomes. In DNA samples from leaves taken 13-41 days after treatment, RFLP (Restriction Fragment Length Polymorphism) patterns were indistinguishable from controls and 5-AC treatments with all probes. Surprising differences in hybridization patterns were seen between DNA from root tips and leaves with the copia-fragment probes.
This article has been cited by other articles:
![]() |
B.-G. Jeon, G. Coppola, S. D Perrault, G.-J. Rho, D. H Betts, and W A. King S-adenosylhomocysteine treatment of adult female fibroblasts alters X-chromosome inactivation and improves in vitro embryo development after somatic cell nuclear transfer Reproduction, June 1, 2008; 135(6): 815 - 828. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Carchilan, M. Delgado, T. Ribeiro, P. Costa-Nunes, A. Caperta, L. Morais-Cecilio, R. N. Jones, W. Viegas, and A. Houben Transcriptionally Active Heterochromatin in Rye B Chromosomes PLANT CELL, June 1, 2007; 19(6): 1738 - 1749. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Koukalova, M. Fojtova, K. Y. Lim, J. Fulnecek, A. R. Leitch, and A. Kovarik Dedifferentiation of Tobacco Cells Is Associated with Ribosomal RNA Gene Hypomethylation, Increased Transcription, and Chromatin Alterations Plant Physiology, September 1, 2005; 139(1): 275 - 286. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Y. Lim, K. Skalicka, B. Koukalova, R. A. Volkov, R. Matyasek, V. Hemleben, A. R. Leitch, and A. Kovarik Dynamic Changes in the Distribution of a Satellite Homologous to Intergenic 26-18S rDNA Spacer in the Evolution of Nicotiana Genetics, April 1, 2004; 166(4): 1935 - 1946. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. P. Santos, R. Abranches, E. Stoger, A. Beven, W. Viegas, and P. J. Shaw The architecture of interphase chromosomes and gene positioning are altered by changes in DNA methylation and histone acetylation J. Cell Sci., January 12, 2002; 115(23): 4597 - 4605. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. S. Heslop-Harrison Comparative Genome Organization in Plants: From Sequence and Markers to Chromatin and Chromosomes PLANT CELL, May 1, 2000; 12(5): 617 - 636. [Abstract] [Full Text] |
||||