A5082081122- DNA Repair Mechanisms
- Genomics and Chromatin Dynamics
- Microtubule and mitosis dynamics
- DNA and Nucleic Acid Chemistry
- Bacterial Genetics and Biotechnology
- Fungal and yeast genetics research
- Cancer-related Molecular Pathways
- RNA and protein synthesis mechanisms
- Epigenetics and DNA Methylation
- CRISPR and Genetic Engineering
- RNA Research and Splicing
- Advanced biosensing and bioanalysis techniques
- RNA modifications and cancer
- Carcinogens and Genotoxicity Assessment
- RNA Interference and Gene Delivery
- Pluripotent Stem Cells Research
- Bacteriophages and microbial interactions
- Cancer therapeutics and mechanisms
- Ubiquitin and proteasome pathways
- Cancer-related gene regulation
- Immune Cell Function and Interaction
- Mitochondrial Function and Pathology
- Plant Genetic and Mutation Studies
- Semiconductor materials and devices
- Chromatin Remodeling and Cancer
Tokyo Metropolitan Institute of Medical Science
2016-2025
The University of Tokyo
1999-2024
Chiba University
2021
Institute of Medical Sciences
2016
Public Health Agency of Canada
2013
University of Guelph
2013
Teikyo Heisei University
2010
Nippon Soken (Japan)
2009
Keio University
2004
Tokyo University of Science
1993-2003
One of the long-standing questions in eukaryotic DNA replication is mechanisms that determine where and when a particular segment genome replicated. Cdc7/Hsk1 conserved kinase required for initiation may affect site selection timing origin firing. We identified rif1Δ, null mutant rif1(+), telomere-binding factor, as an efficient bypass fission yeast hsk1. Extensive deregulation dormant origins over wide range chromosomes occurs rif1Δ presence or absence hydroxyurea (HU). At same time, many...
The inheritance of parental histones across the replication fork is thought to mediate epigenetic memory. Here, we reveal that fission yeast Mrc1 (CLASPIN in humans) binds H3-H4 tetramers and operates as a central coordinator symmetric histone inheritance. mutants key connector domain disrupted segregation lagging strand comparable Mcm2 histone-binding mutants. Both showed clonal asymmetric loss H3K9me-mediated gene silencing. AlphaFold predicted co-chaperoning by Mcm2, with bridging...
Cdc7 kinase, conserved from yeasts to human, plays important roles in DNA replication. However, the mechanisms by which it stimulates initiation of replication remain largely unclear. We have analyzed phosphorylation MCM subunits during cell cycle examining mobility shift on SDS-PAGE. MCM4 chromatin undergoes specific S phase. phosphorylates complexes as well N-terminal polypeptide. Experiments with phospho-amino acid-specific antibodies indicate that phase-specific is due at (S/T)(S/T)P...
Meiosis ensures genetic diversification of gametes and sexual reproduction. For successful meiosis, multiple events such as DNA replication, recombination, chromosome segregation must occur coordinately in a strict regulated order. We investigated the meiotic roles Cdc7 kinase initiation namely, double-strand breaks (DSBs) mediated by Spo11 other coactivating proteins. Genetic analysis using bob1-1 cdc7Delta reveals that is essential for DSBs meiosis I progression. also demonstrate...
huCdc7 encodes a catalytic subunit for<i>Saccharomyces cerevisae</i> Cdc7-related kinase complex of human. ASK, whose expression is cell cycle-regulated, binds and activates in cycle-dependent manner (Kumagai, H., Sato, N., Yamada, M., Mahony, D., Seghezzi, W., Lees, E., Arai, K., Masai, H. (1999) <i>Mol. Cell. Biol.</i> 19, 5083–5095). We have expressed complexed with ASK regulatory using the insect system. To facilitate purification complex, glutathione<i>S</i>-transferase (GST) was fused...
Tipin was originally isolated as a protein interacting with Timeless/Tim1/Tim (Tim), which is known to be involved in both circadian rhythm and cell cycle checkpoint regulation. The endogenous Tim proteins human cells, through the N-terminal segment of each molecule, form complex throughout cycle. are expressed interphase nuclei mostly at constant levels during cycle, small fractions recovered chromatin-enriched S phase. Depletion results reduced growth rate, this may due part inefficient...
Cdc7 kinase regulates DNA replication. However, its role in repair and recombination is poorly understood. Here we describe a pathway that stabilizes the human Cdc7–ASK (activator of S-phase kinase; also called Dbf4), regulation, function cellular responses to compromised Stalled replication evoked stabilization (Dbf4) complex manner dependent on ATR–Chk1-mediated checkpoint signaling interplay with anaphase-promoting complex/cyclosome Cdh1 (APC/C ) ubiquitin ligase. Mechanistically, Chk1...
A novel human protein, ASK (activator of S phase kinase), was identified on the basis its ability to bind Cdc7-related kinase (huCdc7). forms an active complex with huCdc7 that is capable phosphorylating MCM2 protein. appears be major activator huCdc7, since immunodepletion protein from extract accompanied by loss huCdc7-dependent activity. Expression regulated growth factor stimulation, and levels oscillate through cell cycle, reaching a peak during phase. Concomitantly, activity...
Saccharomyces cerevisiae CDC7 encodes a serine/threonine kinase required for G1/S transition, and its related kinases are present in fission yeast as well higher eukaryotes, including humans. Kinase activity of Cdc7 protein depends on the regulatory subunit, Dbf4, which also interacts with replication origins. We have identified him1+ from two-hybrid screening Hsk1, homologue kinase, showed that it subunit Hsk1. Him1, identical to Dfp1, previously an associated molecule binds Hsk1 stimulates...
Embryonic stem (ES) cells can grow rapidly and permanently while maintaining their differentiation capacity. To gain insight into how the cell cycle progression of undifferentiated murine ES is regulated, we have examined expression patterns various replication regulators. Most factors including cyclins, Cdc6, geminin are rather constitutively expressed during cells. Furthermore, transcript levels almost all regulators investigated except for p21 p27 higher in than embryonic fibroblasts...
Abstract A priming mechanism requiring dnaA, dnaB, and dnaC proteins operates on a single-stranded DNA coated with DNA-binding protein. This novel priming, referred to as ABC-priming, requires specific hairpin structure whose stem carries dnaA protein recognition sequence (dnaA box). In conjunction primase polymerase III holoenzyme, ABC-priming can efficiently convert into the duplex replicative form. specifically recognizes binds permits loading of dnaB form prepriming complex containing...
The 3.6-kilobase Bgl II-EcoRI fragment from R1 plasmid containing copA, repA, and the replication origin (ori) was inserted into ColE1-type pUC8. resulting hybrid replicates in extracts prepared both polA- polA+ cells, whereas pUC8 only a extract. This characteristic provides method for assaying repA ori functions. Hybrid plasmids that were either repA- or ori- unable to replicate cell Replication of ori+ restored by complementation defect repA+ vitro. Successful function vitro protein. In...
The E3 ubiquitin ligase Rad18 guides DNA Polymerase eta (Polη) to sites of replication fork stalling and mono-ubiquitinates proliferating cell nuclear antigen (PCNA) facilitate binding Y family trans-lesion synthesis (TLS) polymerases during TLS. However, it is unclear exactly how regulated in response damage activity coordinated with progression through different phases the cycle. Here we identify as a novel substrate essential protein kinase Cdc7 (also termed Dbf4/Drf1-dependent [DDK]). A...