Project description:The selection of replication origins plays a crucial role in eukaryotic DNA replication. However, the mechanisms of origin selection in humans are not yet well-defined. Recent work in yeast has shown that the recruitment of Sld3-Sld7 to origins during G1 is involved in origin selection. In humans, TICRR/TRESLIN and MTBP are the orthologs of Sld3 and Sld7, respectively. In this study, we have mapped the genomic binding locations of TICRR/TRESLIN and MTBP in a population of G1 synchronized cells.
Project description:It has been proposed that ATR kinase senses the completion of DNA replication to initiate the S/G2 transition. In contrast to this model, we show here that the TRESLIN-MTBP complex prevents a premature entry into G2 from early S-phase independently of ATR/CHK1 kinases. TRESLIN-MTBP acts transiently at pre-replication complexes (preRCs) to initiate origin firing and is released after the subsequent recruitment of CDC45. This dynamic behavior of TRESLIN-MTBP implements a monitoring system that checks the activation of replication forks and senses the rate of origin firing to prevent the entry into G2. This system detects the decline in the number of origins of replication that naturally occurs in very late S, which is the signature that cells use to determine the completion of DNA replication and permit the S/G2 transition. Our work introduces TRESLIN-MTBP as a key player in cell cycle control independent of canonical checkpoints.
Project description:The selection of replication origins plays a crucial role in eukaryotic DNA replication. However, the mechanisms of origin selection in humans are not yet well-defined. Recent work in yeast has shown that the recruitment of Sld3-Sld7 to origins during G1 is involved in origin selection. In humans, TICRR/TRESLIN and MTBP are the orthologs of Sld3 and Sld7, respectively. In this study, we have mapped the genomic binding locations of TICRR/TRESLIN and MTBP in asynchronous cells.
Project description:It has been proposed that ATR kinase senses the completion of DNA replication to initiate the S/G2 transition. In contrast to this model, we show here that the TRESLIN-MTBP complex prevents a premature entry into G2 from early S-phase independently of ATR/CHK1 kinases. TRESLIN-MTBP acts transiently at pre-replication complexes (preRCs) to initiate origin firing and is released after the subsequent recruitment of CDC45. This dynamic behavior of TRESLIN-MTBP implements a monitoring system that checks the activation of replication forks and senses the rate of origin firing to prevent the entry into G2. This system detects the decline in the number of origins of replication that naturally occurs in very late S, which is the signature that cells use to determine the completion of DNA replication and permit the S/G2 transition. Our work introduces TRESLIN-MTBP as a key player in cell cycle control independent of canonical checkpoints.
Project description:The selection of replication origins plays a crucial role in eukaryotic DNA replication. However, the mechanisms of origin selection in humans still need to be defined. Recent work in yeast has shown that the recruitment of Sld3-Sld7 to origins during G1 is involved in origin selection. In humans, TICRR/TRESLIN and MTBP are the orthologs of Sld3 and Sld7, respectively. In this study, we have mapped the genomic binding locations of TICRR/TRESLIN and MTBP in cells where loading of MCM2-7 complex has been inhibited by dox-inducible expression of a degradation-resistant Geminin(T25D).
Project description:In this study, we have mapped the binding sites for the MTBP subunit of the Treslin-MTBP complex throughout the human genome by using the CUT&RUN method. Our results have indicated that MTBP associates reproducibly with several tens of thousands of sites in the genome. Many binding sites contain either G4 DNA or an AP-1 motif in a nucleosome-free region at transcription start sites (TSSs) or enhancers, respectively. In addition, this nucleosome-free region is adjacent to a nucleosome containing certain histone marks characteristic of open chromatin that have also been implicated in initiation. We also mapped early initiation zones with EdU-labeling (EdU-seq) and found that these initiation domains contain a large number of MTBP binding sites. Taken together, these findings indicate that Treslin-MTBP associates with multiple genomic signals to promote initiation of replication.
Project description:UCRs expression signature of HCT-116 cell lines versus HCT-116 cell line treated with DNA methylation inhibitor 5-aza-2'-deoxycytidine
Project description:To understand molecular mechanisms underlying the growth inhibitory ativity of Stearoyl-CoA desaturase-1 (SCD1) inhibitor, we performed microarray analysis using HCT-116 colorectal cancer cells, in which SCD1 was pharmacologically blocked or genetically ablated.
Project description:Anti-APC ChIP-seq data were collected from HCT-116 cells and 3,985 genomic sequences were found to be enriched in both independent biological replicates.