ATM, the Mre11/Rad50/Nbs1 complex, and topoisomerase I are concentrated in the nucleus of Purkinje neurons in the juvenile human brain.
The genetic disease ataxia telangiectasia (AT) results from mutations in the ataxia telangiectasia mutated (ATM) gene. AT patients develop a progressive degeneration of cerebellar Purkinje neurons. Surprisingly, while ATM plays a criticial role in the cellular reponse to DNA damage, previous studies have localized ATM to the cytoplasm of rodent and human Purkinje neurons. Here we show that ATM is primarily localized to the nucleus in cerebellar Purkinje neurons in postmortem human brain tissue samples, although some light cytoplasmic ATM staining was also observed. No ATM staining was observed in brain tissue samples from AT patients, verifying the specificity of the antibody. We also found that antibodies against components of the Mre11/Rad50/Nbs1 (MRN) complex showed strong staining in Purkinje cell nuclei. However, while ATM is present in both the nucleoplasm and nucleolus, MRN proteins are excluded from the nucleolus. We also observed very high levels of topoisomerase 1 (TOP1) in the nucleus, and specifically the nucleolus, of human Purkinje neurons. Our results have direct implications for understanding the mechanisms of neurodegeneration in AT and AT-like disorder.
Gorodetsky
Elena
E
Section on Molecular Neurobiology, Laboratory of Neurogenetics, National Institute on Alcohol Abuse and Alcoholism, 5625 Fishers Lane, Room 3S-32, MSC 9412, Bethesda, MD 20952-9412, USA.
Calkins
Sarah
S
Ahn
Julia
J
Brooks
P J
PJ
D017766:Acid Anhydride Hydrolases; D000293:Adolescent; D000328:Adult; D001260:Ataxia Telangiectasia / Q000378:metabolism; D064007:Ataxia Telangiectasia Mutated Proteins; D001921:Brain / Q000254:growth & development / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000032:analysis* / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism*; D045643:DNA Repair Enzymes / Q000032:analysis / Q000378:metabolism; D004264:DNA Topoisomerases, Type I / Q000032:analysis* / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000032:analysis* / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D006801:Humans; D000076228:MRE11 Homologue Protein; D009687:Nuclear Proteins / Q000032:analysis* / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000032:analysis* / Q000378:metabolism; D011689:Purkinje Cells / Q000378:metabolism*; D025521:Tumor Suppressor Proteins / Q000032:analysis* / Q000378:metabolism
D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; C121766:MRE11 protein, human; C112156:NBN protein, human; D009687:Nuclear Proteins; D025521:Tumor Suppressor Proteins; C576324:ATM protein, human; D064007:Ataxia Telangiectasia Mutated Proteins; D017346:Protein Serine-Threonine Kinases; D000076228:MRE11 Homologue Protein; D017766:Acid Anhydride Hydrolases; C112158:RAD50 protein, human; D004264:DNA Topoisomerases, Type I; D045643:DNA Repair Enzymes
Nat Rev Mol Cell Biol. 2002 Jun;3(6):430-40
12042765
J Biol Chem. 2002 May 3;277(18):15661-5
11907023
EMBO J. 2003 Oct 15;22(20):5612-21
14532133
J Biol Chem. 2004 May 21;279(21):21873-82
15014084
DNA Repair (Amst). 2004 Aug-Sep;3(8-9):1141-7
15279803
DNA Repair (Amst). 2004 Aug-Sep;3(8-9):1219-25
15279810
Brain Res Mol Brain Res. 2004 Sep 10;128(1):1-7
15337312
DNA Repair (Amst). 2004 Nov 2;3(11):1515-20
15380107
J Comp Neurol. 1976 May 1;167(1):27-47
818132
EMBO J. 1985 May;4(5):1237-43
2988941
Science. 1995 Jun 23;268(5218):1749-53
7792600
Mol Pathol. 1997 Oct;50(5):247-53
9497914
Neuroscience. 1998 Oct;86(4):1045-54
9697112
Proc Natl Acad Sci U S A. 1998 Aug 18;95(17):10146-51
9707615
Neurosci Lett. 1998 Aug 21;252(3):195-8
9739994
Semin Pediatr Neurol. 1998 Dec;5(4):287-94
9874856
Nat Neurosci. 1999 Feb;2(2):139-43
10195197
Science. 1999 Oct 15;286(5439):552-5
10521354
Brain Res. 1999 Sep 25;842(2):351-8
10526131
J Biol Chem. 2004 Dec 31;279(53):55618-25
15494395
Science. 2005 Apr 22;308(5721):551-4
15790808
J Comp Neurol. 2005 Dec 19;493(3):357-69
16261531
Nat Rev Genet. 2006 May;7(5):373-84
16607398
J Biol Chem. 2006 Jun 23;281(25):17482-91
16627474
J Neurosci. 2006 Jul 19;26(29):7767-74
16855104
Cold Spring Harb Symp Quant Biol. 2005;70:99-109
16869743
Neuroscience. 2006 Sep 15;141(4):1951-9
16784818
Nature. 2006 Sep 14;443(7108):222-5
16906133
Nat Rev Cancer. 2006 Oct;6(10):789-802
16990856
J Comp Neurol. 2007 Jan 1;500(1):71-83
17099896
DNA Repair (Amst). 2007 Jan 4;6(1):128-34
17178256
Trends Biochem Sci. 2006 Jul;31(7):402-10
16774833
J Biol Chem. 1999 Nov 26;274(48):34277-82
10567403
Proc Natl Acad Sci U S A. 2000 Jan 18;97(2):871-6
10639172
Adv Cancer Res. 2001;80:189-216
11034544
J Comp Neurol. 2001 Mar 5;431(2):228-39
11170002
J Neurosci. 2001 Sep 1;21(17):6687-93
11517258
Nat Genet. 2002 Oct;32(2):267-72
12244316