Systematic identification of fragile sites via genome-wide location analysis of gamma-H2AX.
Phosphorylation of histone H2AX is an early response to DNA damage in eukaryotes. In Saccharomyces cerevisiae, DNA damage or replication-fork stalling results in phosphorylation of histone H2A yielding gamma-H2A (yeast gamma-H2AX) in a Mec1 (ATR)- and Tel1 (ATM)-dependent manner. Here, we describe the genome-wide location analysis of gamma-H2A as a strategy to identify loci prone to engaging the Mec1 and Tel1 pathways. Notably, gamma-H2A enrichment overlaps with loci prone to replication-fork stalling and is caused by the action of Mec1 and Tel1, indicating that these loci are prone to breakage. Moreover, about half the sites enriched for gamma-H2A map to repressed protein-coding genes, and histone deacetylases are necessary for formation of gamma-H2A at these loci. Finally, our work indicates that high-resolution mapping of gamma-H2AX is a fruitful route to map fragile sites in eukaryotic genomes.
[1] Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada. [2] These authors contributed equally to this work.
Rachel K
RK
Szilard
Pierre-Etienne
PE
Jacques
Louise
L
Laramée
Benjamin
B
Cheng
Sarah
S
Galicia
Alain R
AR
Bataille
ManTek
M
Yeung
Megan
M
Mendez
Maxime
M
Bergeron
François
F
Robert
Daniel
D
Durocher
D002453:Cell Cycle; D018797:Cell Cycle Proteins / Q000235:genetics / Q000502:physiology; D047369:Chromatin Immunoprecipitation; D016681:Genome, Fungal / Q000235:genetics*; D006657:Histones / Q000235:genetics*; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation; D016133:Polymerase Chain Reaction; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism
D018797:Cell Cycle Proteins; D006657:Histones; D047908:Intracellular Signaling Peptides and Proteins; D029701:Saccharomyces cerevisiae Proteins; C088937:MEC1 protein, S cerevisiae; D017346:Protein Serine-Threonine Kinases; C513623:TEL1 protein, S cerevisiae