| Structural highlights
Function
[MDC1_HUMAN] Required for checkpoint mediated cell cycle arrest in response to DNA damage within both the S phase and G2/M phases of the cell cycle. May serve as a scaffold for the recruitment of DNA repair and signal transduction proteins to discrete foci of DNA damage marked by 'Ser-139' phosphorylation of histone H2AFX. Also required for downstream events subsequent to the recruitment of these proteins. These include phosphorylation and activation of the ATM, CHEK1 and CHEK2 kinases, and stabilization of TP53 and apoptosis. ATM and CHEK2 may also be activated independently by a parallel pathway mediated by TP53BP1.[1] [2] [3] [4] [5] [6] [7] [8] [9] [10]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
MDC1 (mediator of DNA damage checkpoint protein 1) regulates the recognition and repair of DNA double strand breaks in mammalian cells through its interactions with nuclear foci containing the COOH-terminally phosphorylated form of the histone variant, H2AX. Here we demonstrate that the tandem BRCT repeats of MDC1 directly bind to the phosphorylated tail of H2AX-Ser(P)-Gln-Glu-Tyr, in a manner that is critically dependent on the free carboxylate group of the COOH-terminal Tyr residue. We have determined the x-ray crystal structure of the MDC1 BRCT repeats at 1.45 Angstroms resolution. By a comparison with the structure of the BRCA1 BRCT bound to a phosphopeptide, we suggest that two arginine residues in MDC1, Arg(1932) and Arg(1933) may recognize the COOH terminus of the peptide as well as the penultimate Glu of H2AX, while Gln(2013) may provide additional specificity for the COOH-terminal Tyr.
Structure of the BRCT repeat domain of MDC1 and its specificity for the free COOH-terminal end of the gamma-H2AX histone tail.,Lee MS, Edwards RA, Thede GL, Glover JN J Biol Chem. 2005 Sep 16;280(37):32053-6. Epub 2005 Jul 27. PMID:16049003[11]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Mochan TA, Venere M, DiTullio RA Jr, Halazonetis TD. 53BP1 and NFBD1/MDC1-Nbs1 function in parallel interacting pathways activating ataxia-telangiectasia mutated (ATM) in response to DNA damage. Cancer Res. 2003 Dec 15;63(24):8586-91. PMID:14695167
- ↑ Shang YL, Bodero AJ, Chen PL. NFBD1, a novel nuclear protein with signature motifs of FHA and BRCT, and an internal 41-amino acid repeat sequence, is an early participant in DNA damage response. J Biol Chem. 2003 Feb 21;278(8):6323-9. Epub 2002 Dec 9. PMID:12475977 doi:10.1074/jbc.M210749200
- ↑ Xu X, Stern DF. NFBD1/KIAA0170 is a chromatin-associated protein involved in DNA damage signaling pathways. J Biol Chem. 2003 Mar 7;278(10):8795-803. Epub 2002 Dec 23. PMID:12499369 doi:10.1074/jbc.M211392200
- ↑ Peng A, Chen PL. NFBD1, like 53BP1, is an early and redundant transducer mediating Chk2 phosphorylation in response to DNA damage. J Biol Chem. 2003 Mar 14;278(11):8873-6. Epub 2003 Jan 24. PMID:12551934 doi:10.1074/jbc.C300001200
- ↑ Lou Z, Chini CC, Minter-Dykhouse K, Chen J. Mediator of DNA damage checkpoint protein 1 regulates BRCA1 localization and phosphorylation in DNA damage checkpoint control. J Biol Chem. 2003 Apr 18;278(16):13599-602. Epub 2003 Feb 27. PMID:12611903 doi:10.1074/jbc.C300060200
- ↑ Goldberg M, Stucki M, Falck J, D'Amours D, Rahman D, Pappin D, Bartek J, Jackson SP. MDC1 is required for the intra-S-phase DNA damage checkpoint. Nature. 2003 Feb 27;421(6926):952-6. PMID:12607003 doi:10.1038/nature01445
- ↑ Lou Z, Minter-Dykhouse K, Wu X, Chen J. MDC1 is coupled to activated CHK2 in mammalian DNA damage response pathways. Nature. 2003 Feb 27;421(6926):957-61. PMID:12607004 doi:10.1038/nature01447
- ↑ Stewart GS, Wang B, Bignell CR, Taylor AM, Elledge SJ. MDC1 is a mediator of the mammalian DNA damage checkpoint. Nature. 2003 Feb 27;421(6926):961-6. PMID:12607005 doi:10.1038/nature01446
- ↑ Lukas C, Melander F, Stucki M, Falck J, Bekker-Jensen S, Goldberg M, Lerenthal Y, Jackson SP, Bartek J, Lukas J. Mdc1 couples DNA double-strand break recognition by Nbs1 with its H2AX-dependent chromatin retention. EMBO J. 2004 Jul 7;23(13):2674-83. Epub 2004 Jun 17. PMID:15201865 doi:10.1038/sj.emboj.7600269
- ↑ Lou Z, Chen BP, Asaithamby A, Minter-Dykhouse K, Chen DJ, Chen J. MDC1 regulates DNA-PK autophosphorylation in response to DNA damage. J Biol Chem. 2004 Nov 5;279(45):46359-62. Epub 2004 Sep 17. PMID:15377652 doi:10.1074/jbc.C400375200
- ↑ Lee MS, Edwards RA, Thede GL, Glover JN. Structure of the BRCT repeat domain of MDC1 and its specificity for the free COOH-terminal end of the gamma-H2AX histone tail. J Biol Chem. 2005 Sep 16;280(37):32053-6. Epub 2005 Jul 27. PMID:16049003 doi:10.1074/jbc.C500273200
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