ISSN:
1573-675X
Keywords:
apoptosis
;
ATP depletion
;
cell acidification and shrinkage
;
CpG-specific megabase fragmentations
;
DCNP (2,6-dichloro-4-nitrophenol)
;
housekeeping genes
;
microarray (genechip)
;
zVAD-fmk
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Abstract Previous suggestions of CpG-specific apoptotic commitment implied critical epigenetic modulation of house-keeping genes which have canonical CpG islands at 5′ promoter regions. Differential housekeeping gene activity however has not been shown. Using a focussed microarray (genechip) of 22 housekeeping genes we show this in apoptosis induced in human Chang liver cells by DCNP (2,6-dichloro-4-nitrophenol), a non-genotoxic inhibitor of sulfate detoxification. 3–7 folds downregulation of 9 genes in glycolysis, tricarboxylic acid cycle and the respiratory electron transport chain suggested gene-directed energy depletion which was correlated with observed ATP depletion. 4 folds downregulation of the pyruvate dehydrogenease gene suggested gene-directed metabolic acidosis which was correlated with observed cell acidification. Other differential housekeeping gene activity, including 4 folds upregulation of microtubular alpha-tubulin gene, and 2 folds upregulation of ubiquitin, also had a bearing on apoptosis. Broadspectrum zVAD-fmk caspase inhibition abolished 200 bp DNA ladder fragmentations but not the CpG-specific megabase fragmentations and other hallmarks of cell destruction, suggesting a caspase-independent cell death. Death appeared committed at gene-level.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1009695811147
