Transcriptional Activation of a Constitutive Heterochromatic Domain of the Human Genome in Response to Heat ShockD⃞
AUTOR(ES)
Rizzi, Nicoletta
FONTE
The American Society for Cell Biology
RESUMO
Heat shock triggers the assembly of nuclear stress bodies that contain heat shock factor 1 and a subset of RNA processing factors. These structures are formed on the pericentromeric heterochromatic regions of specific human chromosomes, among which chromosome 9. In this article we show that these heterochromatic domains are characterized by an epigenetic status typical of euchromatic regions. Similarly to transcriptionally competent portions of the genome, stress bodies are, in fact, enriched in acetylated histone H4. Acetylation peaks at 6 h of recovery from heat shock. Moreover, heterochromatin markers, such as HP1 and histone H3 methylated on lysine 9, are excluded from these nuclear districts. In addition, heat shock triggers the transient accumulation of RNA molecules, heterogeneous in size, containing the subclass of satellite III sequences found in the pericentromeric heterochromatin of chromosome 9. This is the first report of a transcriptional activation of a constitutive heterochromatic portion of the genome in response to stress stimuli.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=329232Documentos Relacionados
- Repression of the heat shock factor 1 transcriptional activation domain is modulated by constitutive phosphorylation.
- The Role of Heat Shock Transcription Factor 1 in the Genome-wide Regulation of the Mammalian Heat Shock ResponseD⃞
- Temperature-dependent regulation of a heterologous transcriptional activation domain fused to yeast heat shock transcription factor.
- Binding of heat shock factor to and transcriptional activation of heat shock genes in Drosophila.
- Dual control of heat shock response: involvement of a constitutive heat shock element-binding factor.