Article

Nuclear architecture and spatial positioning help establish transcriptional states of telomeres in yeast

Laboratoire de Biologie Cellulaire du Noyau, CNRS URA1773, Institut Pasteur, 25 rue du Dr. Roux, 75724 Paris cedex 15, France.
Nature Cell Biology (impact factor: 19.49). 02/2002; 4(3):214-221. DOI:10.1038/ncb756 pp.214-221

ABSTRACT Recent experiments have shown that gene repression can be correlated with relocation of genes to heterochromatin-rich silent domains. Here, we investigate whether nuclear architecture and spatial positioning can contribute directly to the transcriptional activity of a genetic locus in Saccharomyces cerevisiae. By disassembling telomeric silent domains without altering the chromatin-mediated silencing machinery, we show that the transcriptional activity of silencer–reporter constructs depends on intranuclear position. This demonstrates that telomeric silent domains are actively involved in transcriptional silencing. Employing fluorescent in situ hybridization (FISH) in combination with genetic assays, we demonstrate that telomeres control the establishment of transcriptional states by reversible partitioning with the perinuclear silencing domains. Anchoring telomeres interferes with their ability to assume an active state, whereas disassembly of silencing domains prevents telomeres from assuming a repressed state. Our data support a model in which domains of enriched transcriptional regulators allow genes to determine transcriptional states by spatial positioning.

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Keywords

active state
 
Anchoring telomeres interferes
 
data support
 
disassembling telomeric silent domains
 
Employing fluorescent
 
enriched transcriptional regulators
 
genes
 
genetic assays
 
genetic locus
 
heterochromatin-rich silent domains
 
intranuclear position
 
nuclear architecture
 
Recent experiments
 
repressed state
 
reversible partitioning
 
silencer–reporter constructs
 
telomeres control
 
telomeric silent domains
 
transcriptional activity
 
transcriptional states
 

Frank Feuerbach