Asako Furukohri

Learn More
Escherichia coli dinB encodes the specialized DNA polymerase DinB (Pol IV), which is induced as part of the SOS stress-response system and functions in translesion synthesis (TLS) to relieve the replicative Pol III that is stalled at DNA lesions. As the number of DinB molecules, even in unstressed cells, is greater than that required to accomplish TLS, it(More)
An assay that measures synchronized, processive DNA replication by Escherichia coli DNA polymerase III holoenzyme was used to reveal replacement of pol III by the specialized lesion bypass DNA polymerase IV when the replicative polymerase is stalled. When idled replication is restarted, a rapid burst of pol III-catalyzed synthesis accompanied by(More)
Dbf4 is a regulatory subunit for the Cdc7 protein kinase that is required for the initiation of eukaryotic DNA replication, but the precise roles of Dbf4-Cdc7 remain to be determined. Here we identified a Xenopus homolog of Dbf4 (XDbf4) and characterized XDbf4 and Xenopus Cdc7 (XCdc7) in Xenopus egg extracts. XDbf4 formed a complex with XCdc7 in egg(More)
DNA polymerase IV (Pol IV) is one of three translesion polymerases in Escherichia coli. A mass spectrometry study revealed that single-stranded DNA-binding protein (SSB) in lysates prepared from exponentially-growing cells has a strong affinity for column-immobilized Pol IV. We found that purified SSB binds directly to Pol IV in a pull-down assay, whereas(More)
The Mre11/Rad50 complex is a central player in various genome maintenance pathways. Here, we report a novel mode of nuclease action found for the Escherichia coli Mre11/Rad50 complex, SbcC2/D2 complex (SbcCD). SbcCD cuts off the top of a cruciform DNA by making incisions on both strands and continues cleaving the dsDNA stem at ∼10-bp intervals. Using(More)
The facilitates chromatin transcription (FACT) complex affects nuclear DNA transactions in a chromatin context. Though the involvement of FACT in eukaryotic DNA replication has been revealed, a clear understanding of its biochemical behavior during DNA replication still remains elusive. Here, we analyzed the chromatin-binding dynamics of FACT using Xenopus(More)
Escherichia coli DNA polymerase IV (Pol IV, also known as DinB) is a Y-family DNA polymerase capable of catalyzing translesion DNA synthesis (TLS) on certain DNA lesions, and accumulating data suggest that Pol IV may play an important role in copying various kinds of spontaneous DNA damage including N(2)-dG adducts and alkylated bases. Pol IV has a unique(More)
The SOS response is readily triggered by replication fork stalling caused by DNA damage or a dysfunctional replicative apparatus in Escherichia coli cells. E. coli dinB encodes DinB DNA polymerase and its expression is upregulated during the SOS response. DinB catalyzes translesion DNA synthesis in place of a replicative DNA polymerase III that is stalled(More)
The SOS response is a DNA damage response pathway that serves as a general safeguard of genome integrity in bacteria. Extensive studies of the SOS response in Escherichia coli have contributed to establishing the key concepts of cellular responses to DNA damage. However, how the SOS response impacts on the dynamics of DNA replication fork movement remains(More)
Trinucleotide repeats (TNRs) are highly unstable in genomes, and their expansions are linked to human disorders. DNA replication is reported to be involved in TNR instability, but the current models are insufficient in explaining TNR expansion is induced during replication. Here, we investigated replication fork progression across huntingtin(More)