Mediator of DNA damage checkpoint protein-1 (MDC1) is a recently identified nuclear protein that participates in DNA-damage sensing and signaling. Here we report that knockdown of MDC1 by RNA interference results in cellular hypersensitivity to the DNA cross-linking agent mitomycin C and ionizing radiation and in impaired homology-mediated repair of double-strand breaks in DNA. MDC1 forms a complex with Rad51 through a direct interaction with the forkhead-associated domain of MDC1, not the BRCA1 C-terminal domain. Depletion of MDC1 results in impaired formation of Rad51 ionizing radiation–induced foci, reduced amounts of nuclear and chromatin-bound Rad51, and a corresponding increase in Rad51 protein degradation. Together, our findings suggest that MDC1 functions in Rad51-mediated homologous recombination by retaining Rad51 in chromatin.
Subscribe to Journal
Get full journal access for 1 year
only $4.92 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Tax calculation will be finalised during checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
van Gent, D.C., Hoeijmakers, J.H. & Kanaar, R. Chromosomal stability and the DNA double-stranded break connection. Nat. Rev. Genet. 2, 196–206 (2001).
Thompson, L.H. & Schild, D. Homologous recombinational repair of DNA ensures mammalian chromosome stability. Mutat. Res. 477, 131–153 (2001).
Xu, X. & Stern, D.F. NFBD1/MDC1 regulates ionizing radiation-induced focus formation by DNA checkpoint signaling and repair factors. FASEB J. 17, 1842–1848 (2003).
Xu, X. & Stern, D.F. NFBD1/KIAA0170 is a chromatin-associated protein involved in DNA damage signaling pathways. J. Biol. Chem. 278, 8795–8803 (2003).
Mochan, T.A., Venere, M., DiTullio, R.A., Jr. & Halazonetis, T.D. 53BP1 and NFBD1/MDC1-Nbs1 function in parallel interacting pathways activating ataxia-telangiectasia mutated (ATM) in response to DNA damage. Cancer Res. 63, 8586–8591 (2003).
Stewart, G.S., Wang, B., Bignell, C.R., Taylor, A.M. & Elledge, S.J. MDC1 is a mediator of the mammalian DNA damage checkpoint. Nature 421, 961–966 (2003).
Stucki, M. & Jackson, S.P. MDC1/NFBD1: a key regulator of the DNA damage response in higher eukaryotes. DNA Repair (Amst.) 3, 953–957 (2004).
Goldberg, M. et al. MDC1 is required for the intra-S-phase DNA damage checkpoint. Nature 421, 952–956 (2003).
Lou, Z. et al. MDC1 regulates DNA-PK autophosphorylation in response to DNA damage. J. Biol. Chem. 279, 46359–46362 (2004).
Lou, Z., Chini, C.C., 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. 278, 13599–13602 (2003).
Lou, Z., Minter-Dykhouse, K., Wu, X. & Chen, J. MDC1 is coupled to activated CHK2 in mammalian DNA damage response pathways. Nature 421, 957–961 (2003).
Zhang, J. et al. Chk2 phosphorylation of BRCA1 regulates DNA double-strand break repair. Mol. Cell. Biol. 24, 708–718 (2004).
Callebaut, I. & Mornon, J.P. From BRCA1 to RAP1: a widespread BRCT module closely associated with DNA repair. FEBS Lett. 400, 25–30 (1997).
Hofmann, K. & Bucher, P. The FHA domain: a putative nuclear signalling domain found in protein kinases and transcription factors. Trends Biochem. Sci. 20, 347–349 (1995).
Tsai, M.D. FHA: a signal transduction domain with diverse specificity and function. Structure (Camb). 10, 887–888 (2002).
Pierce, A.J., Johnson, R.D., Thompson, L.H. & Jasin, M. XRCC3 promotes homology-directed repair of DNA damage in mammalian cells. Genes Dev. 13, 2633–2638 (1999).
Durocher, D. et al. The molecular basis of FHA domain: phosphopeptide binding specificity and implications for phospho-dependent signaling mechanisms. Mol. Cell 6, 1169–1182 (2000).
Dimitrova, D.S. & Gilbert, D.M. Stability and nuclear distribution of mammalian replication protein A heterotrimeric complex. Exp. Cell Res. 254, 321–327 (2000).
Vassin, V.M., Wold, M.S. & Borowiec, J.A. Replication protein A (RPA) phosphorylation prevents RPA association with replication centers. Mol. Cell. Biol. 24, 1930–1943 (2004).
Raderschall, E. et al. Elevated levels of Rad51 recombination protein in tumor cells. Cancer Res. 62, 219–225 (2002).
Flygare, J., Benson, F. & Hellgren, D. Expression of the human RAD51 gene during the cell cycle in primary human peripheral blood lymphocytes. Biochim. Biophys. Acta 1312, 231–236 (1996).
Yamamoto, A. et al. Cell cycle-dependent expression of the mouse Rad51 gene in proliferating cells. Mol. Gen. Genet. 251, 1–12 (1996).
Chen, F. et al. Cell cycle-dependent protein expression of mammalian homologs of yeast DNA double-strand break repair genes Rad51 and Rad52. Mutat. Res. 384, 205–211 (1997).
Moynahan, M.E., Chiu, J.W., Koller, B.H. & Jasin, M. Brca1 controls homology-directed DNA repair. Mol. Cell 4, 511–518 (1999).
Moynahan, M.E., Pierce, A.J. & Jasin, M. BRCA2 is required for homology-directed repair of chromosomal breaks. Mol. Cell 7, 263–272 (2001).
Weaver, D.T. What to do at an end: DNA double-strand-break repair. Trends Genet. 11, 388–392 (1995).
Liang, F., Han, M., Romanienko, P.J. & Jasin, M. Homology-directed repair is a major double-strand break repair pathway in mammalian cells. Proc. Natl. Acad. Sci. USA 95, 5172–5177 (1998).
Takata, M. et al. Homologous recombination and non-homologous end-joining pathways of DNA double-strand break repair have overlapping roles in the maintenance of chromosomal integrity in vertebrate cells. EMBO J. 17, 5497–5508 (1998).
Johnson, R.D. & Jasin, M. Double-strand-break-induced homologous recombination in mammalian cells. Biochem. Soc. Trans. 29, 196–201 (2001).
Xu, B., Kim, S.T., Lim, D.S. & Kastan, M.B. Two molecularly distinct G(2)/M checkpoints are induced by ionizing irradiation. Mol. Cell. Biol. 22, 1049–1059 (2002).
Taniguchi, T. et al. Convergence of the fanconi anemia and ataxia telangiectasia signaling pathways. Cell 109, 459–472 (2002).
Xie, A. et al. Control of sister chromatid recombination by histone H2AX. Mol. Cell 16, 1017–1025 (2004).
Miyazaki, T., Bressan, D.A., Shinohara, M., Haber, J.E. & Shinohara, A. In vivo assembly and disassembly of Rad51 and Rad52 complexes during double-strand break repair. EMBO J. 23, 939–949 (2004).
Bishop, D.K. RecA homologs Dmc1 and Rad51 interact to form multiple nuclear complexes prior to meiotic chromosome synapsis. Cell 79, 1081–1092 (1994).
Lukas, C. et al. Mdc1 couples DNA double-strand break recognition by Nbs1 with its H2AX-dependent chromatin retention. EMBO J. 23, 2674–2683 (2004).
Mekeel, K.L. et al. Inactivation of p53 results in high rates of homologous recombination. Oncogene 14, 1847–1857 (1997).
Xia, F. et al. Deficiency of human BRCA2 leads to impaired homologous recombination but maintains normal nonhomologous end joining. Proc. Natl. Acad. Sci. USA 98, 8644–8649 (2001).
Chatterjee, A. et al. Mapping the sites of putative tumor suppressor genes at 6p25 and 6p21.3 in cervical carcinoma: occurrence of allelic deletions in precancerous lesions. Cancer Res. 61, 2119–2123 (2001).
Mendez, J. & Stillman, B. Chromatin association of human origin recognition complex, cdc6, and minichromosome maintenance proteins during the cell cycle: assembly of prereplication complexes in late mitosis. Mol. Cell. Biol. 20, 8602–8612 (2000).
We thank J. Chen and M. Jasin for their generous contribution of materials. This work was supported by Public Health Science grant CA107640 to S.N.P.
The authors declare no competing financial interests.
About this article
Cite this article
Zhang, J., Ma, Z., Treszezamsky, A. et al. MDC1 interacts with Rad51 and facilitates homologous recombination. Nat Struct Mol Biol 12, 902–909 (2005). https://doi.org/10.1038/nsmb991
The Valproate Mediates Radio-Bidirectional Regulation Through RFWD3-Dependent Ubiquitination on Rad51
Frontiers in Oncology (2021)
Nature Genetics (2020)
DNA Repair (2020)
Karyopherin α-2 Mediates MDC1 Nuclear Import through a Functional Nuclear Localization Signal in the tBRCT Domain of MDC1
International Journal of Molecular Sciences (2020)
MiR-7-5p-mediated downregulation of PARP1 impacts DNA homologous recombination repair and resistance to doxorubicin in small cell lung cancer
BMC Cancer (2019)