Genetic interactions between HNT3/Aprataxin and RAD27/FEN1 suggest parallel pathways for 5' end processing during base excision repair.
Mutations in Aprataxin cause the neurodegenerative syndrome ataxia oculomotor apraxia type 1. Aprataxin catalyzes removal of adenosine monophosphate (AMP) from the 5' end of a DNA strand, which results from an aborted attempt to ligate a strand break containing a damaged end. To gain insight into which DNA lesions are substrates for Aprataxin action in vivo, we deleted the Saccharomyces cerevisiae HNT3 gene, which encodes the Aprataxin homolog, in combination with known DNA repair genes. While hnt3Delta single mutants were not sensitive to DNA damaging agents, loss of HNT3 caused synergistic sensitivity to H(2)O(2) in backgrounds that accumulate strand breaks with blocked termini, including apn1Delta apn2Delta tpp1Delta and ntg1Delta ntg2Delta ogg1Delta. Loss of HNT3 in rad27Delta cells, which are deficient in long-patch base excision repair (LP-BER), resulted in synergistic sensitivity to H(2)O(2) and MMS, indicating that Hnt3 and LP-BER provide parallel pathways for processing 5' AMPs. Loss of HNT3 also increased the sister chromatid exchange frequency. Surprisingly, HNT3 deletion partially rescued H(2)O(2) sensitivity in recombination-deficient rad51Delta and rad52Delta cells, suggesting that Hnt3 promotes formation of a repair intermediate that is resolved by recombination.
Daley
James M
JM
Centre de Recherche, Hôpital Maisonneuve-Rosemont, Université de Montréal, Montréal, QC H1T 2M4, Canada.
Wilson
Thomas E
TE
Ramotar
Dindial
D
D000249:Adenosine Monophosphate / Q000378:metabolism; D000478:Alkylation / Q000187:drug effects; D020134:Catalytic Domain; D053960:DNA Breaks / Q000187:drug effects; D004260:DNA Repair; D004271:DNA, Fungal / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism; D045585:Flap Endonucleases / Q000235:genetics*; D017353:Gene Deletion; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D008741:Methyl Methanesulfonate / Q000494:pharmacology; D009687:Nuclear Proteins / Q000737:chemistry / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D010641:Phenotype; D017354:Point Mutation; D051135:Rad51 Recombinase / Q000235:genetics; D051721:Rad52 DNA Repair and Recombination Protein / Q000235:genetics; D011995:Recombination, Genetic; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000187:drug effects / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics*; D016335:Zinc Fingers
C438188:APTX protein, human; D004271:DNA, Fungal; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D051721:Rad52 DNA Repair and Recombination Protein; D029701:Saccharomyces cerevisiae Proteins; D000249:Adenosine Monophosphate; D008741:Methyl Methanesulfonate; D006861:Hydrogen Peroxide; D051135:Rad51 Recombinase; D045585:Flap Endonucleases; C468323:RAD27 protein, S cerevisiae
Science. 1993 Mar 26;259(5103):1896-9
8456314
Proc Natl Acad Sci U S A. 1996 Oct 1;93(20):10729-34
8855248
DNA Repair (Amst). 2008 Jan 1;7(1):67-76
17881298
DNA Repair (Amst). 2004 Nov 2;3(11):1493-502
15380105
J Biol Chem. 1999 Aug 20;274(34):24176-86
10446192
DNA Repair (Amst). 2009 Jun 4;8(6):760-6
19303373
Nature. 2002 Jan 10;415(6868):183-7
11805838
J Biol Chem. 1998 Apr 10;273(15):8842-8
9535864
Nat Genet. 2001 Oct;29(2):184-8
11586299
J Biol Chem. 2003 Aug 15;278(33):31434-43
12783866
Mol Cell Biol. 2009 Mar;29(5):1354-62
19103743
Mol Cell Biol. 1999 Mar;19(3):1800-9
10022867
Mol Cell Biol. 1999 Dec;19(12):8361-71
10567561
Mutat Res. 1994 Apr 1;306(1):35-44
7512201
Cell Mol Life Sci. 2005 Feb;62(4):485-91
15719174
Biochem Biophys Res Commun. 2004 Dec 24;325(4):1279-85
15555565
Nucleic Acids Res. 1996 Apr 1;24(7):1267-71
8614629
Nat Genet. 2001 Oct;29(2):189-93
11586300
Nat Rev Mol Cell Biol. 2003 Jun;4(6):435-45
12778123
Mol Cell Biol. 2001 Nov;21(21):7191-8
11585902
Mol Cell Biol. 2005 Feb;25(3):896-906
15657419
Cell. 1997 Jan 24;88(2):253-63
9008166
Mutat Res. 1999 Jan 26;433(1):33-44
10047777
Science. 2005 Apr 22;308(5721):551-4
15790808
EMBO J. 2008 Jul 23;27(14):1953-62
18596698
Proc Natl Acad Sci U S A. 1991 Mar 1;88(5):1731-5
1848010
Nature. 2006 Oct 12;443(7112):713-6
16964241
J Biol Chem. 2008 Dec 5;283(49):33994-4001
18836178
Radiat Res. 2003 Feb;159(2):251-61
12537531
Int J Radiat Biol Relat Stud Phys Chem Med. 1973 Oct;24(4):397-404
4542925
Nucleic Acids Res. 1994 Aug 11;22(15):3026-32
8065916
Neuroscience. 2007 Apr 14;145(4):1418-25
17224243
Mol Cell Biol. 1991 Sep;11(9):4537-44
1715020
Chem Rev. 2006 Feb;106(2):687-99
16464020
J Biol Chem. 2001 May 4;276(18):15073-81
11278831
J Biol Chem. 1982 Oct 10;257(19):11750-4
7118909
Nucleic Acids Res. 2007;35(11):3797-809
17519253
Cell. 2008 Sep 19;134(6):981-94
18805091
Yeast. 1998 Jan 30;14(2):115-32
9483801
J Biol Chem. 1999 Aug 13;274(33):23599-609
10438542
Proc Natl Acad Sci U S A. 1999 Feb 16;96(4):1303-8
9990019
J Biol Chem. 2007 Mar 30;282(13):9469-9474
17276982
Hum Mol Genet. 2004 May 15;13(10):1081-93
15044383
DNA Repair (Amst). 2009 May 1;8(5):672-9
19264558
J Biol Chem. 2004 Nov 12;279(46):47580-8
15342630
Genes Dev. 1998 Oct 1;12(19):3137-43
9765213
Nature. 2008 Oct 9;455(7214):770-4
18806779
DNA Repair (Amst). 2004 Jan 5;3(1):1-12
14697754