PMID- 19502789
OWN - NLM
STAT- MEDLINE
DCOM- 20091020
LR  - 20211020
IS  - 1551-4005 (Electronic)
IS  - 1538-4101 (Print)
IS  - 1551-4005 (Linking)
VI  - 8
IP  - 14
DP  - 2009 Jul 15
TI  - Cytometric detection of chromatin relaxation, an early reporter of DNA damage 
      response.
PG  - 2233-7
AB  - One of the early events of the DNA damage response (DDR), particularly if the 
      damage involves induction of DNA double-strand breaks, is remodeling of chromatin 
      structure characterized by its relaxation (decondensation). The relaxation 
      increases accessibility of the damaged DNA sites to the repair machinery. We 
      present here a simple cytometric approach to detect chromatin relaxation based on 
      the analysis of the proclivity of DNA in situ to undergo denaturation after 
      treatment with acid. DNA denaturation is probed by the metachromatic fluorochrome 
      acridine orange (AO) which differentially stains single-stranded (denatured) DNA 
      by fluorescing red and the double-stranded DNA by emitting green fluorescence. 
      DNA damage was induced in both human leukemic TK6 cells and mitogen-stimulated 
      human peripheral blood lymphocytes by exposure to UV light or by treatment with 
      H(2)O(2). Chromatin relaxation was revealed by diminished susceptibility of DNA 
      to denaturation, likely reflecting decreased DNA torsional stress, seen as soon 
      as 10 min after subjecting cells to UV or H(2)O(2). While cells in all phases of 
      the cell cycle showed a comparable extent of chromatin relaxation upon UV or 
      H(2)O(2) exposure, H2AX was phosphorylated on Ser139 predominantly in S-phase 
      cells. The data are consistent with the notion that chromatin relaxation is 
      global, affects all cells with damaged DNA, and is a prerequisite to the 
      subsequent steps of DDR that can be selective to cells in a particular phase of 
      the cell cycle. The method offers a rapid and simple means of detecting genotoxic 
      insult on cells.
FAU - Halicka, H Dorota
AU  - Halicka HD
AD  - Brander Cancer Research Institute and Department of Pathology, New York Medical 
      College, Valhalla, NY 10595, USA.
FAU - Zhao, Hong
AU  - Zhao H
FAU - Podhorecka, Monika
AU  - Podhorecka M
FAU - Traganos, Frank
AU  - Traganos F
FAU - Darzynkiewicz, Zbigniew
AU  - Darzynkiewicz Z
LA  - eng
GR  - R01 CA028704/CA/NCI NIH HHS/United States
GR  - R01 CA 28704/CA/NCI NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
DEP - 20090711
PL  - United States
TA  - Cell Cycle
JT  - Cell cycle (Georgetown, Tex.)
JID - 101137841
RN  - 0 (Chromatin)
RN  - 0 (Fluorescent Dyes)
RN  - 0 (H2AX protein, human)
RN  - 0 (Histones)
RN  - BBX060AN9V (Hydrogen Peroxide)
RN  - F30N4O6XVV (Acridine Orange)
SB  - IM
CIN - Cell Cycle. 2009 Jul 15;8(14):2140-1. PMID: 19587543
MH  - Acridine Orange/pharmacology
MH  - Cell Line, Tumor
MH  - Chromatin/*metabolism
MH  - *DNA Damage
MH  - DNA Repair
MH  - Flow Cytometry/*methods
MH  - Fluorescent Dyes/pharmacology
MH  - Histones/*metabolism
MH  - Humans
MH  - Hydrogen Peroxide/pharmacology
MH  - Nucleic Acid Denaturation
MH  - Phosphorylation
MH  - S Phase
MH  - Ultraviolet Rays
PMC - PMC3856216
MID - NIHMS533369
EDAT- 2009/06/09 09:00
MHDA- 2009/10/21 06:00
PMCR- 2013/12/08
CRDT- 2009/06/09 09:00
PHST- 2009/06/09 09:00 [entrez]
PHST- 2009/06/09 09:00 [pubmed]
PHST- 2009/10/21 06:00 [medline]
PHST- 2013/12/08 00:00 [pmc-release]
AID - 8984 [pii]
AID - 10.4161/cc.8.14.8984 [doi]
PST - ppublish
SO  - Cell Cycle. 2009 Jul 15;8(14):2233-7. doi: 10.4161/cc.8.14.8984. Epub 2009 Jul 
      11.