Mouse embryonic stem cells, but not somatic cells, predominantly use homologous recombination to repair double-strand DNA breaks.
Embryonic stem (ES) cells give rise to all cell types of an organism. Since mutations at this embryonic stage would affect all cells and be detrimental to the overall health of an organism, robust mechanisms must exist to ensure that genomic integrity is maintained. To test this proposition, we compared the capacity of murine ES cells to repair DNA double-strand breaks with that of differentiated cells. Of the 2 major pathways that repair double-strand breaks, error-prone nonhomologous end joining (NHEJ) predominated in mouse embryonic fibroblasts, whereas the high fidelity homologous recombinational repair (HRR) predominated in ES cells. Microhomology-mediated end joining, an emerging repair pathway, persisted at low levels in all cell types examined. The levels of proteins involved in HRR and microhomology-mediated end joining were highly elevated in ES cells compared with mouse embryonic fibroblasts, whereas those for NHEJ were quite variable, with DNA Ligase IV expression low in ES cells. The half-life of DNA Ligase IV protein was also low in ES cells. Attempts to increase the abundance of DNA Ligase IV protein by overexpression or inhibition of its degradation, and thereby elevate NHEJ in ES cells, were unsuccessful. When ES cells were induced to differentiate, however, the level of DNA Ligase IV protein increased, as did the capacity to repair by NHEJ. The data suggest that preferential use of HRR rather than NHEJ may lend ES cells an additional layer of genomic protection and that the limited levels of DNA Ligase IV may account for the low level of NHEJ activity.
Tichy
Elisia D
ED
Department of Cell and Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267-0524, USA. tichyed@ucmail.uc.edu
Pillai
Resmi
R
Deng
Li
L
Liang
Li
L
Tischfield
Jay
J
Schwemberger
Sandy J
SJ
Babcock
George F
GF
Stambrook
Peter J
PJ
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D002478:Cells, Cultured; D053903:DNA Breaks, Double-Stranded; D000072481:DNA Ligase ATP; D011088:DNA Ligases / Q000378:metabolism; D004260:DNA Repair; D053595:Embryonic Stem Cells / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D005347:Fibroblasts / Q000166:cytology / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D011995:Recombination, Genetic; D014212:Tretinoin / Q000494:pharmacology
D000970:Antineoplastic Agents; D014212:Tretinoin; D011088:DNA Ligases; D000072481:DNA Ligase ATP
Curr Biol. 1998 Dec 17-31;8(25):1395-8
9889105
Methods Mol Biol. 2002;185:27-33
11768996
DNA Cell Biol. 2003 Feb;22(2):65-78
12713733
Nucleic Acids Res. 2008 Jun;36(10):3297-310
18440984
J Biol Chem. 2000 Nov 3;275(44):34787-96
10945980
Mutat Res. 2002 Jun;511(2):145-78
12052432
DNA Repair (Amst). 2005 Aug 15;4(9):1019-27
15979950
Cancer. 2009 Jul 1;115(13):2816-23
19402169
Mol Cell Biol. 2006 Jan;26(1):131-9
16354685
Stem Cells. 2004;22(6):962-71
15536187
Eur J Med Genet. 2009 Nov-Dec;52(6):373-8
19467349
DNA Repair (Amst). 2008 Oct 1;7(10):1765-71
18675941
Cell. 1998 Dec 23;95(7):891-902
9875844
J Cell Physiol. 2007 Nov;213(2):475-83
17492771
Trends Biochem Sci. 2004 Aug;29(8):409-17
15362224
Cell Cycle. 2008 Sep 15;7(18):2902-6
18769152
J Biol Chem. 2004 Sep 3;279(36):37282-90
15194694
EMBO J. 1997 Nov 17;16(22):6874-85
9362500
J Anti Aging Med. 2003 Spring;6(1):29-39
12941181
DNA Repair (Amst). 2008 Sep 1;7(9):1471-83
18602349
Cancer Res. 2004 Jan 15;64(2):517-22
14744764
Proc Natl Acad Sci U S A. 2002 Mar 19;99(6):3586-90
11891338
DNA Repair (Amst). 2007 May 1;6(5):639-48
17236818
Curr Biol. 1998 Jan 29;8(3):145-55
9443911
Nucleic Acids Res. 2009 Feb;37(2):482-92
19056826
Mol Biol Cell. 2001 Nov;12(11):3386-401
11694575
Cell Death Differ. 2007 Aug;14(8):1422-32
17464330
Oncogene. 1994 Mar;9(3):809-18
8108123
Mech Ageing Dev. 2000 Aug 15;117(1-3):1-19
10958919
Biochim Biophys Acta. 2002 Oct 11;1578(1-3):59-72
12393188
Proc Natl Acad Sci U S A. 2004 May 18;101(20):7624-9
15123826
Proc Natl Acad Sci U S A. 1997 Jul 22;94(15):8076-81
9223317
Genes Dev. 1999 Oct 15;13(20):2633-8
10541549
Nucleic Acids Res. 1991 Dec;19(25):7171-5
1766877
J Cell Physiol. 2007 Feb;210(2):517-26
17096384
Proc Natl Acad Sci U S A. 1996 Jun 25;93(13):6236-40
8692798
Am J Clin Oncol. 2009 Aug;32(4):436-42
19657238
Oncogene. 1999 Feb 25;18(8):1537-44
10102623
Nucleic Acids Res. 1999 Aug 15;27(16):3276-82
10454634
Nature. 2009 May 21;459(7245):460-3
19357644
DNA Repair (Amst). 2006 Feb 3;5(2):189-209
16290067
Mutat Res. 1995 Oct;338(1-6):19-23
7565875
J Biol Chem. 2004 Dec 31;279(53):55117-26
15498778
J Cell Physiol. 2004 Feb;198(2):223-9
14603524
Trends Genet. 2008 Nov;24(11):529-38
18809224
Biochem Biophys Res Commun. 2006 Mar 3;341(1):175-83
16412978
J Cell Sci. 2008 Mar 1;121(Pt 5):590-600
18252799
Genes Dev. 2002 Oct 1;16(19):2485-90
12368259
Genes Dev. 2000 Nov 15;14(22):2807-12
11090128
Curr Biol. 1999 Dec 16-30;9(24):1501-4
10607596
Proc Natl Acad Sci U S A. 2007 Dec 26;104(52):20902-7
18093953
Rev Recent Clin Trials. 2009 May;4(2):110-21
19463107
Proc Natl Acad Sci U S A. 2004 Oct 5;101(40):14443-8
15452351
Stem Cell Rev. 2005;1(2):131-8
17142847
DNA Repair (Amst). 2003 Dec 9;2(12):1405-17
14642568
Transgenic Res. 2003 Dec;12(6):743-6
14713204
Nat Cell Biol. 2006 Aug;8(8):885-90
16845382
Environ Mol Mutagen. 2009 Dec;50(9):815-22
19402155
Biochemistry. 2007 May 1;46(17):4962-76
17407264
J Cell Physiol. 2009 Sep;220(3):586-92
19373864
Proc Natl Acad Sci U S A. 1999 Mar 30;96(7):3911-5
10097137
Proc Natl Acad Sci U S A. 2007 Oct 23;104(43):17046-51
17939999
DNA Repair (Amst). 2002 Dec 5;1(12):1017-26
12531011
DNA Repair (Amst). 2008 Feb 1;7(2):149-61
17964863
Proc Natl Acad Sci U S A. 2000 Jun 6;97(12):6630-3
10823907
EMBO Rep. 2000 Sep;1(3):244-52
11256607
Stem Cells. 2008 Sep;26(9):2266-74
18566332
Oncology (Williston Park). 2009 Apr 15;23(4):342-9
19476264
Mol Cell Biol. 1996 Dec;16(12):7133-43
8943369
Biochemistry. 2000 Jun 20;39(24):7041-9
10852701
Exp Hematol. 1986 Nov;14(10):988-94
3464450
Mol Cell. 2000 Jun;5(6):993-1002
10911993
Genetics. 2007 Jul;176(3):1403-15
17483423
Semin Oncol Nurs. 2009 Aug;25(3):193-202
19635398