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  1. Article ; Online: The transgenic IG-DMR sequence of the mouse Dlk1-Dio3 domain acquired imprinted DNA methylation during the post-fertilization period.

    Matsuzaki, Hitomi / Sugihara, Shokichi / Tanimoto, Keiji

    Epigenetics & chromatin

    2023  Volume 16, Issue 1, Page(s) 7

    Abstract: Background: Allele-specific methylation of the imprinting control region (ICR) is the molecular basis for the genomic imprinting phenomenon that is unique to placental mammals. We previously showed that the ICR at the mouse H19 gene locus (H19 ICR) was ... ...

    Abstract Background: Allele-specific methylation of the imprinting control region (ICR) is the molecular basis for the genomic imprinting phenomenon that is unique to placental mammals. We previously showed that the ICR at the mouse H19 gene locus (H19 ICR) was unexpectedly established after fertilization and not during spermatogenesis in transgenic mice (TgM), and that the same activity was essential for the maintenance of paternal methylation of the H19 ICR at the endogenous locus in pre-implantation embryos. To examine the universality of post-fertilization imprinted methylation across animal species or imprinted loci, we generated TgM with two additional sequences.
    Results: The rat H19 ICR, which is very similar in structure to the mouse H19 ICR, unexpectedly did not acquire imprinted methylation even after fertilization, suggesting a lack of essential sequences in the transgene fragment. In contrast, the mouse IG-DMR, the methylation of which is acquired during spermatogenesis at the endogenous locus, did not acquire methylation in the sperm of TgM, yet became highly methylated in blastocysts after fertilization, but only when the transgene was paternally inherited. Since these two sequences were evaluated at the same genomic site by employing the transgene co-placement strategy, it is likely that the phenotype reflects the intrinsic activity of these fragments rather than position-effect variegation.
    Conclusions: Our results suggested that post-fertilization imprinted methylation is a versatile mechanism for protecting paternal imprinted methylation from reprogramming during the pre-implantation period.
    MeSH term(s) Animals ; Female ; Male ; Mice ; Pregnancy ; Rats ; Calcium-Binding Proteins ; DNA Methylation ; Fertilization ; Genomic Imprinting ; Intercellular Signaling Peptides and Proteins ; Membrane Proteins ; Mice, Transgenic ; Placenta ; RNA, Long Noncoding/genetics ; Semen
    Chemical Substances Calcium-Binding Proteins ; Dlk1 protein, mouse ; Dlk1 protein, rat ; Intercellular Signaling Peptides and Proteins ; Membrane Proteins ; RNA, Long Noncoding
    Language English
    Publishing date 2023-02-17
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2462129-8
    ISSN 1756-8935 ; 1756-8935
    ISSN (online) 1756-8935
    ISSN 1756-8935
    DOI 10.1186/s13072-023-00482-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Genetics of the hypoxia-inducible factors in human cancers.

    Tanimoto, Keiji

    Experimental cell research

    2017  Volume 356, Issue 2, Page(s) 166–172

    Abstract: Professor Lorenz Poellinger (Karolinska Institute/Cancer Science Institute of Singapore) passed away in March 2016. Then hypoxic research field lost a noble and unique researcher when he died, since he had contributed very much to this field in a variety ...

    Abstract Professor Lorenz Poellinger (Karolinska Institute/Cancer Science Institute of Singapore) passed away in March 2016. Then hypoxic research field lost a noble and unique researcher when he died, since he had contributed very much to this field in a variety of aspects. We had been collaborating on a various research projects of genomic analyses of HIF-signaling pathway for a long time, and recently reported several interesting results with HIF-α genes (HIF1A, EPAS1 and HIF3A). Genomics/Genetics is a still growing field, with new technologies appearing often, and many groups have performed extensive genomic/genetic analyses. In this review, I thus focused on the genetics of HIF-α genes in human cancers. I deeply mourn Professor Poellinger's loss and dedicate this review to him.
    MeSH term(s) Animals ; Cell Hypoxia/physiology ; Humans ; Hypoxia/metabolism ; Hypoxia-Inducible Factor 1, alpha Subunit/genetics ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism ; Neoplasms/genetics ; Neoplasms/metabolism ; RNA, Messenger/genetics ; Transcription Factors/genetics
    Chemical Substances Hypoxia-Inducible Factor 1, alpha Subunit ; RNA, Messenger ; Transcription Factors
    Language English
    Publishing date 2017-07-15
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 1493-x
    ISSN 1090-2422 ; 0014-4827
    ISSN (online) 1090-2422
    ISSN 0014-4827
    DOI 10.1016/j.yexcr.2017.03.035
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Five nucleotides found in RCTG motifs are essential for post-fertilization methylation imprinting of the H19 ICR in YAC transgenic mice.

    Matsuzaki, Hitomi / Takahashi, Takuya / Kuramochi, Daichi / Hirakawa, Katsuhiko / Tanimoto, Keiji

    Nucleic acids research

    2023  Volume 51, Issue 14, Page(s) 7236–7253

    Abstract: Genomic imprinting at the mouse Igf2/H19 locus is controlled by the H19 ICR, within which paternal allele-specific DNA methylation originating in sperm is maintained throughout development in offspring. We previously found that a 2.9 kb transgenic H19 ... ...

    Abstract Genomic imprinting at the mouse Igf2/H19 locus is controlled by the H19 ICR, within which paternal allele-specific DNA methylation originating in sperm is maintained throughout development in offspring. We previously found that a 2.9 kb transgenic H19 ICR fragment in mice can be methylated de novo after fertilization only when paternally inherited, despite its unmethylated state in sperm. When the 118 bp sequence responsible for this methylation in transgenic mice was deleted from the endogenous H19 ICR, the methylation level of its paternal allele was significantly reduced after fertilization, suggesting the activity involving this 118 bp sequence is required for methylation maintenance at the endogenous locus. Here, we determined protein binding to the 118 bp sequence using an in vitro binding assay and inferred the binding motif to be RCTG by using a series of mutant competitors. Furthermore, we generated H19 ICR transgenic mice with a 5-bp substitution mutation that disrupts the RCTG motifs within the 118 bp sequence, and observed loss of methylation from the paternally inherited transgene. These results indicate that imprinted methylation of the H19 ICR established de novo during the post-fertilization period involves binding of specific factors to distinct sequence motifs within the 118 bp sequence.
    MeSH term(s) Animals ; Male ; Mice ; DNA Methylation/genetics ; Fertilization ; Genomic Imprinting ; Insulin-Like Growth Factor II/genetics ; Insulin-Like Growth Factor II/metabolism ; Mice, Inbred ICR ; Mice, Transgenic ; RNA, Long Noncoding/genetics ; RNA, Long Noncoding/metabolism ; Semen/metabolism ; Regulatory Sequences, Nucleic Acid
    Chemical Substances Insulin-Like Growth Factor II (67763-97-7) ; RNA, Long Noncoding ; H19 long non-coding RNA
    Language English
    Publishing date 2023-06-19
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 186809-3
    ISSN 1362-4962 ; 1362-4954 ; 0301-5610 ; 0305-1048
    ISSN (online) 1362-4962 ; 1362-4954
    ISSN 0301-5610 ; 0305-1048
    DOI 10.1093/nar/gkad516
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Ribosomal Stress Couples with the Hypoxia Response in Dec1-Dependent Orthodontic Tooth Movement

    Shigeru Nakamura / Keiji Tanimoto / Ujjal K. Bhawal

    International Journal of Molecular Sciences, Vol 24, Iss 1, p

    2022  Volume 618

    Abstract: This study characterized the effects of a deficiency of the hypoxia-responsive gene, differentiated embryonic chondrocyte gene 1 (Dec1), in attenuating the biological function of orthodontic tooth movement (OTM) and examined the roles of ribosomal ... ...

    Abstract This study characterized the effects of a deficiency of the hypoxia-responsive gene, differentiated embryonic chondrocyte gene 1 (Dec1), in attenuating the biological function of orthodontic tooth movement (OTM) and examined the roles of ribosomal proteins in the hypoxic environment during OTM. HIF-1α transgenic mice and control mice were used for hypoxic regulation of periodontal ligament (PDL) fibroblasts. Dec1 knockout ( Dec1 KO) and wild-type (WT) littermate C57BL/6 mice were used as in vivo models of OTM. The unstimulated contralateral side served as a control. In vitro, human PDL fibroblasts were exposed to compression forces for 2, 4, 6, 24, and 48 h. HIF-1α transgenic mice had high expression levels of Dec1, HSP105, and ribosomal proteins compared to control mice. The WT OTM mice displayed increased Dec1 expression in the PDL fibroblasts. Micro-CT analysis showed slower OTM in Dec1 KO mice compared to WT mice. Increased immunostaining of ribosomal proteins was observed in WT OTM mice compared to Dec1 KO OTM mice. Under hypoxia, Dec1 knockdown caused a significant suppression of ribosomal protein expression in PDL fibroblasts. These results reveal that the hypoxic environment in OTM could have implications for the functions of Dec1 and ribosomal proteins to rejuvenate periodontal tissue homeostasis.
    Keywords Dec1 ; ribosomal protein ; HIF-1α ; orthodontic tooth movement ; Biology (General) ; QH301-705.5 ; Chemistry ; QD1-999
    Subject code 570
    Language English
    Publishing date 2022-12-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Orientation of mouse H19 ICR affects imprinted H19 gene expression through promoter methylation-dependent and -independent mechanisms.

    Matsuzaki, Hitomi / Miyajima, Yu / Fukamizu, Akiyoshi / Tanimoto, Keiji

    Communications biology

    2021  Volume 4, Issue 1, Page(s) 1410

    Abstract: The mouse Igf2/H19 locus is regulated by genomic imprinting, in which the paternally methylated H19 imprinting control region (ICR) plays a critical role in mono-allelic expression of the genes in the locus. Although the maternal allele-specific ... ...

    Abstract The mouse Igf2/H19 locus is regulated by genomic imprinting, in which the paternally methylated H19 imprinting control region (ICR) plays a critical role in mono-allelic expression of the genes in the locus. Although the maternal allele-specific insulator activity of the H19 ICR in regulating imprinted Igf2 expression has been well established, the detailed mechanism by which the H19 ICR controls mono-allelic H19 gene expression has not been fully elucidated. In this study, we evaluated the effect of H19 ICR orientation on imprinting regulation in mutant mice in which the H19 ICR sequence was inverted at the endogenous locus. When the inverted-ICR allele was paternally inherited, the methylation level of the H19 promoter was decreased and the H19 gene was derepressed, suggesting that methylation of the H19 promoter is essential for complete repression of H19 gene expression. Unexpectedly, when the inverted allele was maternally inherited, the expression level of the H19 gene was lower than that of the WT allele, even though the H19 promoter remained fully hypomethylated. These observations suggested that the polarity of the H19 ICR is involved in controlling imprinted H19 gene expression on each parental allele, dependent or independent on DNA methylation of the H19 promoter.
    MeSH term(s) Animals ; Gene Expression ; Methylation ; Mice ; Promoter Regions, Genetic
    Language English
    Publishing date 2021-12-17
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 2399-3642
    ISSN (online) 2399-3642
    DOI 10.1038/s42003-021-02939-9
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Oncogenic Role of ADAM32 in Hepatoblastoma: A Potential Molecular Target for Therapy.

    Fukazawa, Takahiro / Tanimoto, Keiji / Yamaoka, Emi / Kojima, Masato / Kanawa, Masami / Hirohashi, Nobuyuki / Hiyama, Eiso

    Cancers

    2022  Volume 14, Issue 19

    Abstract: Outcomes of pediatric hepatoblastoma (HBL) have improved, but refractory cases still occur. More effective and safer drugs are needed that are based on molecular mechanisms. A disintegrin and metalloproteases (ADAMs) are expressed with high frequency in ... ...

    Abstract Outcomes of pediatric hepatoblastoma (HBL) have improved, but refractory cases still occur. More effective and safer drugs are needed that are based on molecular mechanisms. A disintegrin and metalloproteases (ADAMs) are expressed with high frequency in various human carcinomas and play an important role in cancer progression. In this study, we analyzed expression of
    Language English
    Publishing date 2022-09-28
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2527080-1
    ISSN 2072-6694
    ISSN 2072-6694
    DOI 10.3390/cancers14194732
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: p53 status modifies cytotoxic activity of lactoferrin under hypoxic conditions.

    Kosim, Maryami Yuliana / Fukazawa, Takahiro / Miyauchi, Mutsumi / Hirohashi, Nobuyuki / Tanimoto, Keiji

    Frontiers in pharmacology

    2022  Volume 13, Page(s) 988335

    Abstract: Lactoferrin (LF) is an iron binding glycoprotein of the transferrin family with a wide spectrum of biological effects, including anti-cancer activity. However, the detailed molecular mechanisms of anti-cancer activity of LF have not been fully determined. ...

    Abstract Lactoferrin (LF) is an iron binding glycoprotein of the transferrin family with a wide spectrum of biological effects, including anti-cancer activity. However, the detailed molecular mechanisms of anti-cancer activity of LF have not been fully determined. In this study, we tried to clarify cytotoxic functions of LF on various cell lines under hypoxic conditions and elucidate those molecular mechanisms. Cytotoxic activity of LF on cell lines was found to have a range of sensitivities. Hypoxia decreased sensitivity to LF in KD (lip fibroblast) but increased that in HSC2 (oral squamous cell carcinoma). Expression analyses further revealed that LF treatments increased hypoxic HIF-1α, -2α and p53 proteins in KD but attenuated them in HSC2 cells, and decreased HIF-1 target gene,
    Language English
    Publishing date 2022-09-19
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2587355-6
    ISSN 1663-9812
    ISSN 1663-9812
    DOI 10.3389/fphar.2022.988335
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Coexpression of natural killer cell antigens by T-cell large granular lymphocytes in hydroa vacciniforme lymphoproliferative disorder and the involvement of Vδ1 + epithelial-type γδT cells.

    Hirai, Yoji / Iwatsuki, Keiji / Takahashi, Takahide / Miyake, Tomoko / Nakagawa, Yuki / Tanimoto, Shogo / Kawakami, Yoshio / Morizane, Shin

    International journal of hematology

    2023  Volume 118, Issue 1, Page(s) 54–64

    Abstract: Hydroa vacciniforme lymphoproliferative disorder (HV-LPD) is a cutaneous variant of chronic active Epstein-Barr virus disease. We examined the coexpression of T- and natural killer (NK)-cell antigens in five patients with classic HV (cHV) and five with ... ...

    Abstract Hydroa vacciniforme lymphoproliferative disorder (HV-LPD) is a cutaneous variant of chronic active Epstein-Barr virus disease. We examined the coexpression of T- and natural killer (NK)-cell antigens in five patients with classic HV (cHV) and five with systemic HV (sHV). T-cell receptor (TCR) repertoire analysis was performed with high‑throughput sequencing. All five cHV patients had increased γδT cells (> 5%), whereas five sHV patients showed γδT- and αβT-cell dominance in two patients each, and a mixture of abnormal γδT and αβT cells in one. Circulating CD3 + T cells expressed CD16/CD56 at 7.8-42.3% and 1.1-9.7% in sHV and cHV, respectively. The percentage of CD16/CD56 + T cells was higher in the large granular lymphocyte or atypical T-cell fractions in sHV, but no TCR Vα24 invariant chain characteristic of NKT cells was detected. Considerable numbers of CD3 + cells expressing CD56 were observed in sHV skin infiltrates. Of the circulating γδT cells tested, TCR Vδ1 + cells characteristic of the epithelial type of γδT cells were dominant in two sHV cases. Thus, atypical αβT and γδT cells in HV-LPD can express NK-cell antigens, such as CD16 and CD56, and Vδ1 + epithelial-type γδT cells are a major cell type in some HV-LPD cases.
    MeSH term(s) Humans ; Epstein-Barr Virus Infections ; Hydroa Vacciniforme ; Herpesvirus 4, Human ; Killer Cells, Natural ; Lymphoproliferative Disorders
    Language English
    Publishing date 2023-05-03
    Publishing country Japan
    Document type Journal Article
    ZDB-ID 1076875-0
    ISSN 1865-3774 ; 0917-1258 ; 0925-5710
    ISSN (online) 1865-3774
    ISSN 0917-1258 ; 0925-5710
    DOI 10.1007/s12185-023-03599-7
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Transient establishment of imprinted DNA methylation of transgenic human IC1 sequence in mouse during the preimplantation period.

    Hirakawa, Katsuhiko / Matsuzaki, Hitomi / Tanimoto, Keiji

    Human molecular genetics

    2020  Volume 29, Issue 22, Page(s) 3646–3661

    Abstract: Monoallelic gene expression at the Igf2/H19 locus is controlled by paternal allele-specific DNA methylation of the imprinting control region (H19 ICR) that is established during spermatogenesis. We demonstrated that the H19 ICR fragment in transgenic ... ...

    Abstract Monoallelic gene expression at the Igf2/H19 locus is controlled by paternal allele-specific DNA methylation of the imprinting control region (H19 ICR) that is established during spermatogenesis. We demonstrated that the H19 ICR fragment in transgenic mice acquires allele-specific methylation only after fertilization, which is essential for maintaining its allelic methylation during early embryogenesis. We identified a DNA element required for establishing postfertilization methylation within a 118 bp (m118) region. A previously generated knock-in mouse whose endogenous H19 ICR was substituted with the human H19 ICR (hIC1; 4.8 kb) sequence revealed that the hIC1 sequence was partially methylated in sperm, although this methylation was lost by the blastocyst stage, which we assume is due to a lack of an m118-equivalent sequence in the hIC1 transgene. To identify a cis sequence involved in postfertilization methylation within the hIC1 region, we generated three transgenic mouse lines (TgM): one carrying an 8.8 kb hIC1 sequence joined to m118 (hIC1+m118), one with the 8.8 kb hIC1 and one with the 5.8 kb hIC1 sequence joined to m118 (hIC1-3'+m118). We found that the hIC1-3' region was resistant to de novo DNA methylation throughout development. In contrast, the 5' portion of the hIC1 (hIC1-5') in both hIC1+m118 and hIC1 TgM were preferentially methylated on the paternal allele only during preimplantation. As DNA methylation levels were higher in hIC1+m118, the m118 sequence could also induce imprinted methylation of the human sequence. Most importantly, the hIC1-5' sequence appears to possess an activity equivalent to that of m118.
    MeSH term(s) Alleles ; Animals ; CCCTC-Binding Factor/genetics ; DNA Methylation/genetics ; Embryonic Development/genetics ; Gene Expression Regulation/genetics ; Genomic Imprinting/genetics ; Humans ; Insulin-Like Growth Factor II/genetics ; Male ; Mice ; Mice, Transgenic ; RNA, Long Noncoding/genetics ; Spermatogenesis/genetics ; Spermatozoa/growth & development ; Spermatozoa/pathology
    Chemical Substances CCCTC-Binding Factor ; H19 long non-coding RNA ; IGF2 protein, human ; RNA, Long Noncoding ; Insulin-Like Growth Factor II (67763-97-7)
    Language English
    Publishing date 2020-11-30
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1108742-0
    ISSN 1460-2083 ; 0964-6906
    ISSN (online) 1460-2083
    ISSN 0964-6906
    DOI 10.1093/hmg/ddaa253
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Achaete-scute family bHLH transcription factor 2 activation promotes hepatoblastoma progression.

    Kato, Yutaka / Fukazawa, Takahiro / Tanimoto, Keiji / Kanawa, Masami / Kojima, Masato / Saeki, Isamu / Kurihara, Sho / Touge, Ryo / Hirohashi, Nobuyuki / Okada, Satoshi / Hiyama, Eiso

    Cancer science

    2024  Volume 115, Issue 3, Page(s) 847–858

    Abstract: Achaete-scute family bHLH transcription factor 2 (ASCL2) is highly expressed in hepatoblastoma (HB) tissues, but its role remains unclear. Thus, biological changes in the HB cell line HepG2 in response to induced ASCL2 expression were assessed. ASCL2 ... ...

    Abstract Achaete-scute family bHLH transcription factor 2 (ASCL2) is highly expressed in hepatoblastoma (HB) tissues, but its role remains unclear. Thus, biological changes in the HB cell line HepG2 in response to induced ASCL2 expression were assessed. ASCL2 expression was induced in HepG2 cells using the Tet-On 3G system, which includes doxycycline. Cell viability, proliferation activity, mobility, and stemness were evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, colony-formation, migration, invasion, and sphere-formation assays. Quantitative reverse-transcription polymerase chain reaction was used to assess the expression of markers for proliferation (CCND1 and MYC), epithelial-mesenchymal transition (EMT; SNAI1, TWIST1, and ZEB1), mesenchymal-epithelial transition (CDH1), and stemness (KLF4, POU5F1, and SOX9). Compared with the non-induced HepG2 cells, cells with induced ASCL2 expression showed significant increases in viability, colony number, migration area (%), and sphere number on days 7, 14, 8, and 7, respectively, and invasion area (%) after 90 h. Furthermore, induction of ASCL2 expression significantly upregulated CCND1, MYC, POU5F1, SOX9, and KLF4 expression on days 2, 2, 3, 3, and 5, respectively, and increased the ratios of SNAI1, TWIST1, and ZEB1 to CDH1 on day 5. ASCL2 promoted the formation of malignant phenotypes in HepG2 cells, which may be correlated with the upregulation of the Wnt signaling pathway-, EMT-, and stemness-related genes. ASCL2 activation may therefore be involved in the progression of HB.
    MeSH term(s) Humans ; Basic Helix-Loop-Helix Transcription Factors/genetics ; Basic Helix-Loop-Helix Transcription Factors/metabolism ; Hepatoblastoma/genetics ; Cell Line, Tumor ; Gene Expression Regulation, Neoplastic ; Epithelial-Mesenchymal Transition/genetics ; Liver Neoplasms/genetics
    Chemical Substances Basic Helix-Loop-Helix Transcription Factors ; ASCL2 protein, human
    Language English
    Publishing date 2024-01-05
    Publishing country England
    Document type Journal Article
    ZDB-ID 2115647-5
    ISSN 1349-7006 ; 1349-7006
    ISSN (online) 1349-7006
    ISSN 1349-7006
    DOI 10.1111/cas.16051
    Database MEDical Literature Analysis and Retrieval System OnLINE

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