|
|
GEO help: Mouse over screen elements for information. |
|
Status |
Public on May 19, 2011 |
Title |
Expression profiling of nhp6 mutants and wildtype yeast cells (Saccharomyces cerevisiae) |
Platform organisms |
Schizosaccharomyces pombe; Saccharomyces cerevisiae |
Sample organism |
Saccharomyces cerevisiae |
Experiment type |
Expression profiling by array
|
Summary |
The basic unit of genome packaging is the nucleosome, and nucleosomes have long been proposed to restrict DNA accessibility both to damage and to transcription. However, nucleosome number in cells was considered fixed, and no condition was described where nucleosome number was reduced. We show here that mammalian cells lacking High Mobility Group Box 1 protein (HMGB1) contain a reduced amount of core, linker and variant histones, and a correspondingly reduced number of nucleosomes. Yeast nhp6 mutants lacking NHP6A and –B proteins, which are related to HMGB1, also have a reduced amount of histones and fewer nucleosomes. Nucleosome limitation in both mammalian and yeast cells increases the sensitivity of DNA to damage, increases transcription globally, and the relative expression of about 10% of genes. In yeast nhp6 cells the loss of more than one nucleosome in four does not affect the location of nucleosomes and their spacing, but nucleosomal occupancy. The decrease in nucleosomal occupancy is non-uniform, and our results can be modelled assuming that different nucleosomal sites compete for the available histones: sites with high affinity are almost always packaged into nucleosomes both in wt and nucleosome-depleted cells, whereas sites with low affinity are less frequently packaged in nucleosome-depleted cells. We suggest that by modulating the occupancy of nucleosomes histone availability may constitute a novel layer of epigenetic regulation.
|
|
|
Overall design |
This microarray experiment forms part of a larger study of the effects of nucleosome depletion on transcription Using the Affymetrix Yeast Genome 2.0 Array, yeast nhp6 mutants (lacking NHP6A and NHP6B proteins) were compared to wildtype yeast cells (3 biological replicates per condition)
|
|
|
Contributor(s) |
Celona B, Weiner A, Di Felice F, Mancuso FM, Cesarini E, Rossi RL, Gregory L, Baban D, Lockstone H, Rossetti G, Pagani M, Bonaldi T, Ragoussis J, Friedman N, Camilloni G, Bianchi ME, Agresti A |
Citation(s) |
21738444 |
|
Submission date |
Aug 19, 2010 |
Last update date |
Feb 21, 2017 |
Contact name |
Jiannis Ragoussis |
E-mail(s) |
ioannis.ragoussis@well.ox.ac.uk
|
Organization name |
Wellcome Trust Centre For Human Genetics, University of Oxford
|
Lab |
Genomics Research Group
|
Street address |
Roosevelt Drive
|
City |
Oxford |
ZIP/Postal code |
OX3 7BN |
Country |
United Kingdom |
|
|
Platforms (1) |
GPL2529 |
[Yeast_2] Affymetrix Yeast Genome 2.0 Array |
|
Samples (6)
|
|
Relations |
BioProject |
PRJNA130889 |
Supplementary file |
Size |
Download |
File type/resource |
GSE23711_RAW.tar |
5.7 Mb |
(http)(custom) |
TAR (of CEL) |
Processed data included within Sample table |
|
|
|
|
|