Niedzwiedz W, Mosedale G, Johnson M, Ong CY, Pace P, Patel KJ.. The Fanconi anaemia gene FANCC promotes homologous recombination and error-prone DNA repair. Mol Cell 15: 607-620

MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, United Kingdom.
Molecular Cell (Impact Factor: 14.02). 09/2004; 15(4):607-20. DOI: 10.1016/j.molcel.2004.08.009
Source: PubMed


The Fanconi anemia (FA) protein FANCC is essential for chromosome stability in vertebrate cells, a feature underscored by the extreme sensitivity of FANCC-deficient cells to agents that crosslink DNA. However, it is not known how this FA protein facilitates the repair of both endogenously acquired and mutagen-induced DNA damage. Here, we use the model vertebrate cell line DT40 to address this question. We discover that apart from functioning in homologous recombination, FANCC also promotes the mutational repair of endogenously generated abasic sites. Moreover in these vertebrate cells, the efficient repair of crosslinks requires the combined functions of FANCC, translesion synthesis, and homologous recombination. These studies reveal that the FA proteins cooperate with key mutagenesis and repair processes that enable replication of damaged DNA.

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    • "Analyses of DNA Fibers, SCEs, and Chromosomal Aberrations Cells were prepared for analyses of DNA fibers, SCEs, and chromosomal aberrations as described (Niedzwiedz et al., 2004; Schwab et al., 2010). "
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    • "A future challenge is to determine how the various genome maintenance functions of BRCA1 contribute to tumor suppression . Interestingly, the crosslink sensitivity of BRCA1-deficient cells is less severe than for those carrying mutations in other ICL repair factors (Bridge et al., 2005; Niedzwiedz et al., 2004; Ohashi et al., 2005; Qing et al., 2011). This could be explained by the fact that a polymerase-linked mechanism can promote helicase unloading in the absence of BRCA1. "
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    Full-text · Article · Sep 2014 · Molecular Cell
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    • "We developed a purification strategy to isolate the FA core complex from chicken DT40 cells, a vertebrate model used extensively in the study of the FA pathway (Niedzwiedz et al., 2004; Yamamoto et al., 2003). Our aim was to generate a cell line where the only copy of the FANCB subunit included an affinity purification tag (Figure 1A). "
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    ABSTRACT: Fanconi anaemia (FA) is a cancer predisposition syndrome characterized by cellular sensitivity to DNA interstrand crosslinkers. The molecular defect in FA is an impaired DNA repair pathway. The critical event in activating this pathway is monoubiquitination of FANCD2. In vivo, a multisubunit FA core complex catalyzes this step, but its mechanism is unclear. Here, we report purification of a native avian FA core complex and biochemical reconstitution of FANCD2 monoubiquitination. This demonstrates that the catalytic FANCL E3 ligase subunit must be embedded within the complex for maximal activity and site specificity. We genetically and biochemically define a minimal subcomplex comprising just three proteins (FANCB, FANCL, and FAAP100) that functions as the monoubiquitination module. Residual FANCD2 monoubiquitination activity is retained in cells defective for other FA core complex subunits. This work describes the in vitro reconstitution and characterization of this multisubunit monoubiquitin E3 ligase, providing key insight into the conserved FA DNA repair pathway.
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