A5067147854- Reproductive Biology and Fertility
- Epigenetics and DNA Methylation
- Genomics and Chromatin Dynamics
- Pluripotent Stem Cells Research
- RNA Research and Splicing
- Animal Genetics and Reproduction
- Neurobiology and Insect Physiology Research
- Genetic and Clinical Aspects of Sex Determination and Chromosomal Abnormalities
- Sperm and Testicular Function
- CRISPR and Genetic Engineering
- Silkworms and Sericulture Research
- Renal and related cancers
- DNA Repair Mechanisms
- Cancer-related Molecular Pathways
- Reproductive System and Pregnancy
- RNA modifications and cancer
- Insect Resistance and Genetics
- Prenatal Screening and Diagnostics
- Viral Infectious Diseases and Gene Expression in Insects
- Animal Behavior and Reproduction
- Histone Deacetylase Inhibitors Research
- Invertebrate Immune Response Mechanisms
- Milk Quality and Mastitis in Dairy Cows
- Cancer-related molecular mechanisms research
- Insect and Arachnid Ecology and Behavior
The University of Tokyo
2015-2024
Grieg Seafood (Norway)
2019
Institute of Animal Science
2016
Ube Frontier University
2001-2011
University of Pennsylvania
1999-2005
Tokyo University of Science
1995-2002
National Institute of Genetics
1999
Tokyo University of Agriculture
1985-1995
Hokkaido University
1995
National Institute for Basic Biology
1995
In mice, transcription initiates at the mid-one-cell stage and transcriptional activity dramatically increases during two-cell stage, a process called zygotic gene activation (ZGA). Associated with ZGA is marked change in pattern of expression that occurs after second round DNA replication. To distinguish before second-round replication, former latter are minor major ZGA, respectively. Although required for development beyond function not well understood. Transiently inhibiting 5,...
We examined global changes in the acetylation of histones mouse oocytes during meiosis. Immunocytochemistry with specific antibodies against various acetylated lysine residues on H3 and H4 showed that all lysines decreased to undetectable or negligible levels meiosis, whereas most these were mitosis preimplantation embryos somatic cells. When cell nuclei transferred into enucleated oocytes, markedly. This type deacetylation was inhibited by trichostatin A, a inhibitor histone deacetylase...
ABSTRACT p34cdc2 protein kinase is a universal regulator of M-phase in eukaryotic cell cycle. To investigate the regulation meiotic and mitotic cycle mammals, we examined changes phosphorylation states its histone Hl activity mouse oocytes embryos. We showed that p34cde2 has three different migrating bands (referred to as upper, middle lower bands) on SDS-PAGE followed by immunoblotting with anti- PSTAIR antibody, upper are phosphorylated forms since these two shifted one alkaline...
Epigenetic modifications of the genome, such as covalent modification histone residues, ensure appropriate gene activation during pre-implantation development, and are probably involved in asymmetric reprogramming parental genomes after fertilization. We investigated methylation patterns H3 at lysine 9 (H3/K9), regulatory mechanism remodeling early preimplantation development mice. Immunocytochemistry with an antibody that specifically recognizes methylated H3/K9 showed a very weak or absent...
During oocyte growth, chromatin structure is altered globally and gene expression silenced. To investigate the involvement of epigenetic modifications in regulation these phenomena, changes global DNA methylation various histone modifications, i.e. acetylation H3K9, H3K18, H4K5, H4K12, H3K4 were examined during growth mouse oocytes. Immunocytochemical analysis revealed that signal intensities all increased fully grown, germinal vesicle (GV)-stage oocytes showed most modifications. Since...
Errors in meiotic chromosome segregation are the leading cause of spontaneous abortions and birth defects. Almost all such aneuploidy derives from errors females, with increasing maternal age representing a major risk factor. It was recently reported that histones globally deacetylated mammalian oocytes during meiosis but not mitosis. In present study, inhibition histone deacetylation found to induce fertilized mouse oocytes, which resulted embryonic death utero at an early stage...
Retrotransposons are “copy-and-paste” insertional mutagens that substantially contribute to mammalian genome content. often carry long terminal repeats (LTRs) for retrovirus-like reverse transcription and integration into the genome. We report an extraordinary impact of a group LTRs from endogenous retrovirus-related ERVL retrotransposon class on gene expression in germline beyond. In mouse, we identified more than 800 ORR1, MT, MT2, MLT families, which resemble mobile gene-remodeling...
Upon fertilization, reprogramming of gene expression is required for embryo development. This step marked by DNA demethylation and changes in histone variant composition. However, little known about the molecular mechanisms causing these their impact on modifications. We examined global deposition replication-dependent H3.1 H3.2 variants replication-independent H3.3 after fertilization mice. showed that H3.3, a euchromatic marker activity, transiently disappears from maternal genome,...
Abstract During oogenesis, mRNA is actively transcribed and accumulated in growing oocytes, but this transcription stops before the oocytes grow to their full size. The maternal used for protein synthesis during meiotic maturation even embryos sustain development after fertilization. Therefore, degradation of starts maturation, its rate slow. Nevertheless, some species should rapidly degrade fertilization if they encode proteins that play a role specific events meiosis are detrimental In...
In general, cloning undifferentiated preimplantation embryos (blastomeres) or embryonic stem cells is more efficient than differentiated somatic cells. Therefore, there has been an assumption that tissue-specific might serve as donors for nuclear transfer because of the state their genome. Here, we show this not case with adult hematopoietic (HSCs). Although have demonstrated first time mouse HSCs can be cloned to generate offspring, birth rates (0-0.7%) were lowest among clones tested...
Mammals have two types of full-grown oocytes: those with germinal vesicles (GVs) in which the chromatin is condensed and surrounds nucleolus (surrounded-nucleolus (SN)-type) less does not surround (non-surrounded-nucleolus (NSN)-type). Although SN oocytes possess higher meiotic developmental competence than NSN oocytes, factors underlying this difference are unknown.The GVs murine were exchanged by nuclear transfer nucleus/cytoplasm each reconstructed oocyte was classified as follows: SN/SN,...
The gene expression pattern of differentiated oocytes is reprogrammed into that totipotent preimplantation embryos before and/or after fertilization. To elucidate the mechanisms genome reprogramming, we investigated histone H3 lysine 79 dimethylation (H3K79me2) and trimethylation (H3K79me3) in via immunocytochemistry. In somatic cells oocytes, H3K79me2 was observed throughout genome, whereas H3K79me3 localized pericentromeric heterochromatin regions which there are no active genes. Because...
Histone H2A has several variants, and changes in chromatin composition associated with their replacement might involve structure remodeling. We examined the dynamics of canonical histone its three H2A.X, H2A.Z macroH2A, mouse during oogenesis pre-implantation development when genome remodeling occurs. Immunocytochemistry specific antibodies revealed that, although all variants were deposited nuclei full-grown oocytes, only H2A.X was abundant pronuclei one-cell embryos after fertilization,...
The involvement of cumulus cells and chromatin organisation in transcriptional activity was investigated. In addition, the relationship between meiotic competence fully grown mouse oocytes surveyed. Transcriptional detected which did not surround nucleolus germinal vesicle (NSN-type oocytes), but surrounded (SN-type oocytes). Cumulus seemed to downregulate NSN-type oocytes, since 3 times greater denuded free (DO oocytes) than enclosed (COC Higher corresponded lower breakdown (GVB) culture....
To investigate the involvement of mitogen-activated protein kinase (MAP kinase) in meiotic maturation porcine oocytes, we assayed MAP activity using myelin basic (MBP) as a substrate. was low during germinal vesicle stage, 0-20 h culture. An abrupt increase observed at metaphase I (30 culture), and remained significantly higher than that 0 until 50 culture, with transient slight decrease time first polar body extrusion (40 h). Detection by an in-gel phosphorylation assay confirmed 42 44 kDa...
Zygotes are totipotent cells that have the ability to differentiate into all cell types. It is believed this lost gradually and differentiation occurs along with progression of preimplantation development. Here, we hypothesized loose chromatin structure involved in totipotency one-cell stage embryos change from tight associated loss totipotency. To address hypothesis, investigated mobility eGFP-tagged histone H2B (eGFP-H2B), which an index for looseness chromatin, during development based on...
Mitogen-activated protein kinase (MAP kinase) plays a role in the cascade of activation cultured cells. To investigate involvement MAP meiotic maturation, we measured activity, using myelin basic as substrate, with histone H1 mouse oocytes. activity was low 1 h after isolation from follicles (when oocytes lost their germinal vesicle), increased abruptly at 2 h, and remained high until second metaphase (13 follicles). Histone gradually to 7 isolation. When immature were treated puromycin, did...
The objective of the present study was to understand molecular/biochemical nature chromatin remodeling that occurs in somatic nuclei transferred into oocytes. We produced reconstructed mouse embryos by two different protocols nuclear transfer. nucleus a cumulus cell enucleated unfertilized oocytes (transferred before activation, TA protocol) or activated (activated transfer, AT protocol). More than half (56.1%) using protocol developed morula/blastocyst stage, whereas very few (1.0%) reached...
Nuclear core histone modifications influence chromosome structures and functions. Recently, the involvement of acetylations in cell memory gene expression has been suggested mouse oocyte maturation. At present, there is little available data on mammalian In present study, we examined changes acetylation H3 lysines 9 (H3K9) 14 (H3K14), H4 5 (H4K5), 8 (H4K8) 12 (H4K12), trimethylation H3K9 during vitro maturation porcine oocytes. Immunocytochemical analyses revealed that all were highly...
Histone acetylation is an important epigenetic modification implicated in the regulation of chromatin structure and, subsequently, gene expression. Global histone deacetylation was reported mouse oocytes during meiosis but not mitosis. The this meiosis-specific has been elucidated. Here, we demonstrate that p34(cdc2) kinase activity and protein synthesis are responsible for activation deacetylases inhibition acetyltransferases (HATs), respectively, resulting H4 at lysine-12 (H4K12) oocyte...
In <I>Drosophila melanogaster, transformer-2 (tra-2)</I> is essential for female differentiation and known to induce female-specific splicing of <I>doublesex (dsx)</I>. The function <I>Bmtra-2</I>, the <I>Bombyx mori</I> homolog <I>tra-2</I>, on other hand remains be elucidated. As an initial step learn about biological we determined whether <I>Bmtra-2</I> capable inducing dsx</I>. RNAi-mediated knockdown using <I>Bombyx</I> cultured cells transiently transfected with a <I>dsx</I> minigene...
The oocyte-to-embryo transition (OET) transforms a differentiated gamete into pluripotent blastomeres. accompanying maternal-zygotic RNA exchange involves remodeling of the long non-coding (lncRNA) pool. Here, we used next generation sequencing and de novo transcript assembly to define core population 1,600 lncRNAs expressed during OET (lncRNAs). Relative mRNAs, were less had shorter transcripts, mainly due fewer exons 5' terminal exons. Approximately half lncRNA promoters originated in...