Here, we describe a cellfree system based on xenopus egg extracts that supports icl repair. Crosslinking of dna an overview sciencedirect topics. Disturbed this icl repair orchestration in s phase causes genome instability resulting a cancer prone disease, fanconi anemia. Dna interstrand crosslink repair during g1 involves nucleotide excision repair and dna polymerase zeta. Fanconi anemia proteins, dna interstrand crosslink repair. A single icl can kill repair deficient bacteria and yeast, and about 40 icls can kill repair deficient mammalian cells. Dna interstrand crosslinks icls are among the most toxic dna damages. Recent studies have revealed the mechanisms and the.
In genetics, crosslinking of dna occurs when various exogenous or endogenous agents react with two nucleotides of dna, forming a covalent linkage between them. Seidman, dna interstrand crosslink repair in mammalian cells. Additionally, some compounds widely used in anticancer therapies, such as mitomycin c. Dna interstrand crosslinks icls are toxic dna lesions whose repair occurs in the s phase of metazoans via an unknown mechanism. Dna interstrand crosslinks icls are formed by bifunctional agents and covalently link two strands of a dna duplex. Adpribosylation by adpribosyltransferases arts has a wellestablished role in dna strand break repair by promoting enrichment of repair factors at damage sites through adpribose interaction domains. The role of adpribosylation in regulating dna interstrand.
Fanconi anemia, interstrand crosslink repair and cancer. Pmc free article this paper describes an important icl repair mechanism that is active in g1 phase of the cell cycle. Human dna helicase helq participates in dna interstrand. Novel crosslinking agents, and targeting strategies involving dna crosslinking agents, continue to be developed. Snm1bapollo in the dna damage response and telomere. Agents that cause dna interstrand crosslinks are widely used to treat cancer. The fanconi anemia pathway promotes replicationdependent. Icls physically block cellular processes that require the unwinding of the dna molecule, such as replication, recombination, and transcription. Involvement of translesion synthesis dna polymerases in. To investigate the possibility of measuring the genespecific dna damage after therapeutic exposure to nitrogen mustards and to examine its relationship with the clinical response. To repair interstrand crosslinks in eukaryotes, a 3 flap endonuclease from the ner. Translesion dna synthesis polymerases in dna interstrand.
In genetics, crosslinking of dna occurs when various exogenous or endogenous agents react. Here, we exploit the simple eukaryote dictyostelium to uncover a role for adpribosylation in regulating dna interstrand crosslink repair and redundancy of this pathway with non. Agents that induce icls were one of the earliest, and are. Icls can be repaired by the fanconi anemia fa pathway and through faindependent processes involving the fan1 nuclease. However, cellular responses triggered by icls can cause resistance in tumor cells, limiting the efficacy of such treatment. In this work, fan1 dna crystal structures and biochemical data reveal that human fan1 cleaves dna successively at every third nucleotide. West abstract interstrand crosslinks icls are highly toxic dna lesions that prevent transcription and. These adducts interfere with cellular metabolism, such as dna replication and transcription, triggering cell.
Interstrand crosslinks, which link the two complementary strands of dna together, comprise less than 5% of the total dna lesions but are highly cytotoxic and difficult to repair 8. Request pdf on jan 22, 20, taraswi banerjee and others published fanconi anemia, interstrand crosslink repair and cancer find, read and cite all the research you need on researchgate. Dna interstrand crosslinks icls are extremely cytotoxic, but the. The role of brca2 in replicationcoupled dna interstrand crosslink repair in vitro. Icls are repaired during and outside s phase, and replicationindependent icl repair rir is critical to maintain genomic integrity and to allow transcription in nondividing or slowly dividing cells. Sensing and processing of dna interstrand crosslinks by. Although hsf2bp was previously described as testisspecific, we find it is.
The role of slx4 in dna interstrand crosslink repair hubrecht. The proteins involved in icl repair, in general, are required for resistance to icls and. Snm1a is involved in the repair of icls and disruption of snm1a leads to. The preferential damage of mtdna and the absence of crosslink repair further suggests that mtdna may be a biologically important target for psoralen. In response to dna interstrand crosslinks icls, fancd2 coordinates several dna repair mechanisms in order to promote genome stability, yet its connection to homologous recombination hr is poorly understood. They can be formed by endogenous sources such as products of lipid metabolism and abasic sites, as well as by a number of antitumor agents such as nitrogen mustards, cisplatin and mitomycin c.
During dna replication of a plasmid containing a sitespecific icl, two replication forks converge on the crosslink. Since the icl lesion affects both strands of the dna, the icl repair is not simple. Journal dna interstrand crosslink repair during g1. Interstrand crosslinks icls are amongst the most cytotoxic dna lesions, covalently. Mechanism of replicationcoupled dna interstrand crosslink. We show that a functionally uncharacterized protein, hsf2bp, is involved in a novel, direct and highly evolutionarily conserved interaction with brca2.
Mechanism of replicationcoupled dna interstrand crosslink repair. The main repair pathway in escherichia coli involves the sequential action of nucleotide excision repair ner and recombinational repair. Understanding the cellular response to dna damage induced by these agents is critical for more effective utilization of these compounds and for the. Replication fork reversal during dna interstrand crosslink repair. The kinetics of genespecific monoadducts and interstrand crosslink formation repair were measured in the p53 and n ras genes. Cancer treatments have been engineered using dna crosslinking agents to interact. Sequential use of three dna repair pathways to repair dna crosslinks. Dna interstrand crosslink repair in mammalian cells. The role of brca2 in replicationcoupled dna interstrand. A number of dna damaging agents broadly utilized in cancer treatment induce dna interstrand crosslinks icls 1114. Mechanism of dna interstrand crosslink processing by. Unrepaired icls often lead to cell death, a trait that is exploited in cancer chemotherapy by using icl inducing agents to kill cancer cells.
Fork reversal requires replicative cmg helicase unloading. Cisplatin sensitivity of testis tumour cells is due to deficiency in interstrandcrosslink repair and low ercc1xpf expression. Replication fork reversal during dna interstrand crosslink. Drugs that produce dna interstrand crosslinks icls, between the two complementary strands of the double helix, have an important role in chemotherapy regimens for cancer. Dna interstrand crosslinkers, a chemically diverse group of compounds which also induce alkylation of bases and dna intrastrand crosslinks, are extensively utilized for cancer therapy. Fa is characterized by genomic instability and cellular sensitivity to dna interstrand cross linking agents. The discovery of a safe mechanism that reverses such damage might open up. Biallelic mutations of fancd2 and other components of the fanconi anemia fa pathway cause a disease characterized by bone marrow failure, cancer predisposition and a striking sensitivity to agents that induce crosslinks between the two complementary dna strands interstrand crosslinks icl. Icl repair that involves a reversed fork intermediate. Intrastrand crosslinks can be readily removed by the nucleotide excision repair ner mechanism. Dna interstrand crosslink repair and cancer nature. Dna interstrand crosslinks icls are lesions that covalently link opposing strands of the double helix. Repair of icls involves multiple dna repair pathways. Dna interstrand crosslinks, with emphasis on repair, cell signaling, and therapeutic implications.
An icl, however, constitutes an absolute block to dna. In vertebrates, icls repair is coupled to replication and involves structurespeci. Pdf fanconi anemia proteins, dna interstrand crosslink. This crosslink can occur within the same strand intrastrand or between opposite strands of doublestranded dna interstrand. Dna interstrand crosslink repair during g1 involves nucleotide excision repair and dna polymerase f sovan sarkar1, adelina a davies2, helle d ulrich2 and peter j mchugh1, 1cancer research uk laboratories, weatherall institute of molecular medicine, university of. Genetic deletion of ercc1 in the mouse causes dramatically accelerated aging. Dna interstrand crosslinks icls are highly toxic lesions associated with cancer and degenerative diseases. Here we discuss recent advances in our understanding of the. Mechanisms of interstrand dna crosslink repair and human. Interstrand dna crosslinks icls are the link between watsoncrick strands of dnas with the covalent bond and prevent separation of dna strands. Replicationindependent repair of dna interstrand crosslinks. Reduced recruitment of 53bp1 during interstrand crosslink repair is.
Parameswary a muniandy, jia liu, alokes majumdar, suting liu and michael m. Introduction dna interstrand crosslinks icls impede dna replication and transcription and are therefore extremely cytotoxic. The tumor suppressor brca2 is essential for homologous recombination, replication fork stability and dna interstrand crosslink icl repair in vertebrates. Translesion dna synthesis polymerases in dna interstrand crosslink repair the vinh ho department of pharmacological sciences, stony brook university, stony brook, new york 11794. Dna interstrand crosslink repair and cancer andrew j. Fanconi anemia is a human cancer predisposition syndrome caused by mutations in fanc genes. Dna crosslinking damage and cancer a tale of friend and foe. Interstrand dna crosslinks icls make up a particular subtype of dna lesions, and these lesions have an especially potent biological effect. The ability of cells to repair dna icls is a critical determinant of sensitivity, and recent clinical studies. Hsf2bp negatively regulates homologous recombination in. They show that ctip is tethered to damaged chromatin by. Since many of these agents are of importance in genetic toxicology and cancer therapy, repair of interstrand crosslinks has been studied extensively in bacteria and in lower and higher eukaryotes. Repair of dna interstrand crosslinks sciencedirect. A central event in the activation of the fanconi anemia pathway is the monoubiquitylation of the fancifancd2 complex, but how this.
Deficiency of dna repair nuclease ercc1xpf promotes. Only recently, however, have we begun to understand how cells repair these lesions. This is the first report on the kinetics of genespecific monoadducts and dna interstrand crosslink formation and repair in a readily accessible tissue of cancer patients after. Histone h2ax phosphorylation as a molecular pharmacological marker for dna interstrand crosslink cancer chemotherapy. So far, nucleotide excision repair ner, structurespecific endonucleases, translesion dna synthesis tls, homologous recombination hr, and factors. Dna crosslinking damage occurs when crosslinking agents covalently connect two nucleotide residues from the same dna strand intrastrand crosslink or from opposite strands interstrand crosslink icl.
Mechanism of rad51dependent dna interstrand crosslink repair. Genespecific formation and repair of dna monoadducts and. Moreover, icls can induce mutations and rearrangements of dna, possibly resulting in uncontrolled cell growth and tumor formation. Mutations in fa proteins give rise to fanconi anemia, a cancer predisposition syndrome. Dna interstrand crosslinks icls are extremely cytotoxic lesions that are mainly repaired in a replicationcoupled manner. Many cancer chemotherapeutic agents form dna interstrand crosslinks icls, extremely cytotoxic lesions that form covalent bonds between two opposing dna strands, blocking dna replication and transcription. In vertebrate cells, dna interstrand crosslink icl repair is coupled to dna replication and involves structurespecific endonucleases, translesion dna polymerases, recombinases, and numerous proteins mutated in the human disease fanconi anemia fa. Dna interstrand crosslinks induced by psoralen are not repaired in mammalian mitochondria cancer research. Mechanism of dna interstrand crosslink processing by repair nuclease fan1 dna interstrand crosslinks icls are highly toxic lesions associated with cancer and.
Dna interstrand crosslinks icls are cytotoxic lesions that covalently link opposite strands of the dna helix and block dna unwinding. Indirect evidence suggests that in metazoans, the principal. Agents that induce icls were one of the earliest, and are still the most widely used, forms of chemotherapeutic drug. Covalent dna protein crosslinks dpcs are induced by various compounds, which include widely used anticancer drugs, and are highly cytotoxic. We have recently shown enhanced repair of dna interstrand crosslinks in ovarian cancer cells from patients following treatment. Crosslink structure affects replicationindependent dna interstrand crosslink repair in mammalian cells. Dna interstrand crosslinks, with emphasis on repair, cell.
1190 1177 402 1179 143 639 172 419 1655 1536 30 92 678 463 380 1577 581 1273 1086 1333 1428 429 169 827 167 1153 977 1403 1558 1043 217 372 1177 1572 1089 1301 1368 422 845 1078 917 354 1372 432 536 1135 911