Kimi Araki

Kumamoto University, Kumamoto, Kumamoto, Japan

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Publications (136)609.42 Total impact

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    ABSTRACT: Colorectal cancer (CRC) is a major cause of deaths due to cancer; therefore, research into its etiology is urgently needed. Although it is clear that chronic inflammation is a risk factor for CRC, the details remains uncertain. Serine protease inhibitor Kazal type 1 (SPINK1) is mainly produced in pancreatic acinar cells. However, SPINK1 is expressed in various cancers and in inflammatory states such as colon cancer and inflammatory bowel disease. There are structural similarities between SPINK1 and epidermal growth factor (EGF). Hence, it was hypothesized that SPINK1 functions as a growth factor for tissue repair in inflammatory states, and if prolonged, acts as a promoter for cell proliferation in cancerous tissues. Here, immunohistochemical (IHC) staining for SPINK1 was observed in a high percentage of CRC patient specimens and SPINK1 induced proliferation of human colon cancer cell lines. To clarify its role in colon cancer in vivo, a mouse model exposed to the colon carcinogen azoxymethane (AOM) and nongenotoxic carcinogen dextran sodium sulfate (DSS) revealed that Spink3 (mouse homolog of Spink1) is overexpressed in cancerous tissues. In Spink3 heterozygous mice, tumor multiplicity and tumor volume were significantly decreased compared with wild-type mice. These results suggest that SPINK1/Spink3 stimulates the proliferation of colon cancer cells, and is involved in CRC progression. Evidence suggests that SPINK1 is an important growth factor that connects chronic inflammation and cancer. Copyright © 2015, American Association for Cancer Research.
    Molecular Cancer Research 03/2015; DOI:10.1158/1541-7786.MCR-14-0581 · 4.50 Impact Factor
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    ABSTRACT: The Dystonin gene (Dst) is responsible for dystonia musculorum (dt), an inherited mouse model of hereditary neuropathy accompanied by progressive motor symptoms such as dystonia and cerebellar ataxia. Dst-a isoforms, which contain actin-binding domains, are predominantly expressed in the nervous system. Although sensory neuron degeneration in the peripheral nervous system during the early postnatal stage is a well-recognised phenotype in dt, the histological characteristics and neuronal circuits in the central nervous system responsible for motor symptoms remain unclear. To analyse the causative neuronal networks and roles of Dst isoforms, we generated novel multipurpose Dst gene trap mice, in which actin-binding domain-containing isoforms are disrupted. Homozygous mice showed typical dt phenotypes with sensory degeneration and progressive motor symptoms. The gene trap allele (DstGt) encodes a mutant Dystonin-LacZ fusion protein, which is detectable by X-gal (5-bromo-4-chloro-3-indolyl-β-D-galactoside) staining. We observed wide expression of the actin-binding domain-containing Dystonin isoforms in the central nervous system (CNS) and peripheral nervous system. This raised the possibility that not only secondary neuronal defects in the CNS subsequent to peripheral sensory degeneration but also cell-autonomous defects in the CNS contribute to the motor symptoms. Expression analysis of immediate early genes revealed decreased neuronal activity in the cerebellar-thalamo-striatal pathway in the homozygous brain, implying the involvement of this pathway in the dt phenotype. These novel DstGt mice showed that a loss-of-function mutation in the actin-binding domain-containing Dystonin isoforms led to typical dt phenotypes. Furthermore, this novel multipurpose DstGt allele offers a unique tool for analysing the causative neuronal networks involved in the dt phenotype.
    European Journal of Neuroscience 09/2014; 40(10). DOI:10.1111/ejn.12711 · 3.67 Impact Factor
  • PLoS ONE 08/2014; 9(8). DOI:10.1371/journal.pone.0106125 · 3.53 Impact Factor
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    ABSTRACT: 2q23.1 microdeletion syndrome is characterized by intellectual disability, motor delay, autistic-like behaviors, and a distinctive craniofacial phenotype. All patients carry a partial or total deletion of methyl-CpG-binding domain protein 5 (MBD5), suggesting that haploinsufficiency of this gene is responsible for the phenotype. To confirm this hypothesis and to examine the role of MBD5 in vivo, we have generated and characterized an Mbd5 gene-trap mouse model. Our study indicates that the Mbd5+/GT mouse model recapitulates most of the hallmark phenotypes observed in 2q23.1 deletion carriers including abnormal social behavior, cognitive impairment, and motor and craniofacial abnormalities. In addition, neuronal cultures uncovered a deficiency in neurite outgrowth. These findings support a causal role of MBD5 in 2q23.1 microdeletion syndrome and suggest a role for MBD5 in neuronal processes. The Mbd5+/GT mouse model will advance our understanding of the abnormal brain development underlying the emergence of 2q23.1 deletion-associated behavioral and cognitive symptoms. Subject Categories Genetics, Gene Therapy & Genetic Disease; Neuroscience
    EMBO Molecular Medicine 07/2014; 6(8). DOI:10.15252/emmm.201404044 · 8.25 Impact Factor
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    ABSTRACT: The Beclin 1-Vps34 complex, the core component of the class III phosphatidylinositol-3 kinase (PI3K-III), binds Atg14L or UVRAG to control different steps of autophagy. However, the mechanism underlying the control of PI3K-III activity remains elusive. Here we report the identification of NRBF2 as a component in the specific PI3K-III complex and a modulator of PI3K-III activity. Through its microtubule interaction and trafficking (MIT) domain, NRBF2 binds Atg14L directly and enhances Atg14L-linked Vps34 kinase activity and autophagy induction. NRBF2-deficient cells exhibit enhanced vulnerability to endoplasmic reticulum (ER) stress that is reversed by re-introducing exogenous NRBF2. NRBF2-deficient mice develop focal liver necrosis and ductular reaction, accompanied by impaired Atg14L-linked Vps34 activity and autophagy, although the mice show no increased mortality. Our data reveal a key role for NRBF2 in the assembly of the specific Atg14L-Beclin 1-Vps34-Vps15 complex for autophagy induction. Thus, NRBF2 modulates autophagy via regulation of PI3K-III and prevents ER stress-mediated cytotoxicity and liver injury.
    Nature Communications 05/2014; 5:3920. DOI:10.1038/ncomms4920 · 10.74 Impact Factor
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    ABSTRACT: Tissue damage by oxidative stress is a key pathogenic mechanism in various diseases, including AKI and CKD. Thus, early detection of oxidative tissue damage is important. Using a tRNA-specific modified nucleoside 1-methyladenosine (m1A) antibody, we show that oxidative stress induces a direct conformational change in tRNA structure that promotes subsequent tRNA fragmentation and occurs much earlier than DNA damage. In various models of tissue damage (ischemic reperfusion, toxic injury, and irradiation), the levels of circulating tRNA derivatives increased rapidly. In humans, the levels of circulating tRNA derivatives also increased under conditions of acute renal ischemia, even before levels of other known tissue damage markers increased. Notably, the level of circulating free m1A correlated with mortality in the general population (n=1033) over a mean follow-up of 6.7 years. Compared with healthy controls, patients with CKD had higher levels of circulating free m1A, which were reduced by treatment with pitavastatin (2 mg/d; n=29). Therefore, tRNA damage reflects early oxidative stress damage, and detection of tRNA damage may be a useful tool for identifying organ damage and forming a clinical prognosis.
    Journal of the American Society of Nephrology 05/2014; 25(10). DOI:10.1681/ASN.2013091001 · 9.47 Impact Factor
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    ABSTRACT: Genome editing with site-specific nucleases, such as zinc-finger nucleases or transcription activator-like effector nucleases (TALENs), and RNA-guided nucleases, such as the CRISPR/Cas (clustered regularly interspaced short palindromic repeats/CRISPR-associated) system, is becoming the new standard for targeted genome modification in various organisms. Application of these techniques to the manufacture of knockout mice would be greatly aided by simple and easy methods for genotyping of mutant and wild-type pups among litters. However, there are no detailed or comparative reports concerning the identification of mutant mice generated using genome editing technologies. Here, we genotyped TALEN-derived enhanced green fluorescent protein (eGFP) knockout mice using a combination of approaches, including fluorescence observation, heteroduplex mobility assay, restriction fragment length polymorphism analysis and DNA sequencing. The detection sensitivities for TALEN-induced mutations differed among these methods, and we therefore concluded that combinatorial testing is necessary for the screening and determination of mutant genotypes. Since the analytical methods tested can be carried out without specialized equipment, costly reagents and/or sophisticated protocols, our report should be of interest to a broad range of researchers who are considering the application of genome editing technologies in various organisms.
    Experimental Animals 04/2014; 63(1):79-84. DOI:10.1538/expanim.63.79 · 1.17 Impact Factor
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    ABSTRACT: Autophagy is an intracellular degradation system in eukaryotic cells that occurs at a basal level. It can also be induced in response to environmental signals including nutrients, hormones, microbial pathogens, and growth factors, although the mechanism is not known in detail. We previously demonstrated that excessive autophagy is induced within pancreatic acinar cells deficient in Spink3, which is a trypsin inhibitor. SPINK1, the human homolog of murine Spink3, has structural similarity to epidermal growth factor (EGF), and can bind and stimulate the EGF receptor (EGFR). To analyze the role of the EGFR in pancreatic development, in the regulation of autophagy in pancreatic acinar cells, and in cerulein-induced pancreatitis, we generated and examined acinar cell-specific Egfr-deficient (Egfr-/-) mice. Egfr-/- mice showed no abnormalities in pancreatic development, induction of autophagy, or cerulein-induced pancreatitis, suggesting that Egfr is dispensable for autophagy regulation in pancreatic acinar cells.
    Biochemical and Biophysical Research Communications 03/2014; 446(1). DOI:10.1016/j.bbrc.2014.02.111 · 2.28 Impact Factor
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    ABSTRACT: mTOR is an evolutionarily conserved kinase that plays a critical role in sensing and responding to environmental determinants. Recent studies have shown that fine-tuning of the activity of mTOR complexes contributes to organogenesis and tumorigenesis. Although rapamycin, an allosteric mTOR inhibitor, is an effective immunosuppressant, the precise roles of mTOR complexes in early T-cell development remain unclear. Here we show that mTORC1 plays a critical role in the development of both early T-cell progenitors and leukemia. Deletion of Raptor, an essential component of mTORC1, produced defects in the earliest development of T-cell progenitors in vivo and in vitro. Deficiency of Raptor resulted in cell cycle abnormalities in early T-cell progenitors that were associated with instability of the Cyclin D2/D3-CDK6 complexes; deficiency of Rictor, an mTORC2 component, did not have the same effect, indicating that mTORC1 and -2 control T-cell development in different ways. In a model of myeloproliferative neoplasm and T-cell acute lymphoblastic leukemia (T-ALL) evoked by Kras activation, Raptor deficiency dramatically inhibited the cell cycle in oncogenic Kras-expressing T-cell progenitors, but not myeloid progenitors, and specifically prevented the development of T-ALL. Although rapamycin treatment significantly prolonged the survival of recipient mice bearing T-ALL cells, rapamycin-insensitive leukemia cells continued to propagate in vivo. In contrast, Raptor deficiency in the T-ALL model resulted in cell cycle arrest and efficient eradication of leukemia. Thus, understanding the cell-context-dependent role of mTORC1 illustrates the potential importance of mTOR signals as therapeutic targets.
    Proceedings of the National Academy of Sciences 02/2014; 111(10). DOI:10.1073/pnas.1320265111 · 9.81 Impact Factor
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    ABSTRACT: Knock-in mouse models have contributed tremendously to our understanding of human disorders. However, generation of knock-in animals requires a significant investment of time and effort. We addressed this problem by developing a novel knock-in system that circumvents several traditional challenges by establishing stem cells with acceptor elements enveloping a particular genomic target. Once established, these acceptor embryonic stem (ES) cells are efficient at directionally incorporating mutated target DNA using modified Cre/lox technology. This is advantageous, because knock-ins are not restricted to one a priori selected variation. Rather, it is possible to generate several mutant animal lines harboring desired alterations in the targeted area. Acceptor ES cell generation is the rate-limiting step, lasting approximately 2 months. Subsequent manipulations toward animal production require an additional 8 weeks, but this delimits the full period from conception of the genetic alteration to its animal incorporation. We call this system a "kick-in" to emphasize its unique characteristics of speed and convenience. To demonstrate the functionality of the kick-in methodology, we generated two mouse lines with separate mutant versions of the voltage-dependent potassium channel Kv7.2 (Kcnq2): p.Tyr284Cys (Y284C) and p.Ala306Thr (A306T); both variations have been associated with benign familial neonatal epilepsy. Adult mice homozygous for Y284C, heretofore unexamined in animals, presented with spontaneous seizures, whereas A306T homozygotes died early. Heterozygous mice of both lines showed increased sensitivity to pentylenetetrazole, possibly due to a reduction in M-current in CA1 hippocampal pyramidal neurons. Our observations for the A306T animals match those obtained with traditional knock-in technology, demonstrating that the kick-in system can readily generate mice bearing various mutations, making it a suitable feeder technology toward streamlined phenotyping.
    PLoS ONE 02/2014; 9(2):e88549. DOI:10.1371/journal.pone.0088549 · 3.53 Impact Factor
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    ABSTRACT: Serine protease inhibitor Kazal type 1 (SPINK1; mouse homologue Spink3) was initially discovered as a trypsin-specific inhibitor in the pancreas. However, previous studies have suggested that SPINK1/Spink3 is expressed in a wide range of normal tissues and tumors, although precise characterization of its gene expression has not been described in adulthood. To further analyze Spink3 expression, we generated two mouse lines in which either lacZ or Cre recombinase genes were inserted into the Spink3 locus by Cre-loxP technology. In Spink3(lacZ) mice, β-galactosidase activity was found in acinar cells of the pancreas and kidney, as well as epithelial cells of the bronchus in the lung, but not in the gastrointestinal tract or liver. Spink3(cre) knock-in mice were crossed with Rosa26 reporter (R26R) mice to monitor Spink3 promoter activity. In Spink3(cre);R26R mice, β-galactosidase activity was found in acinar cells of the pancreas, kidney, lung, and a small proportion of cells in the gastrointestinal tract and liver. These data suggest that Spink3 is widely expressed in endoderm-derived tissues, and that Spink3(cre) knock-in mice are a useful tool for establishment of a conditional knockout mice to analyze Spink3 function not only in normal tissues, but also in tumors that express SPINK1/Spink3.
    Experimental Animals 02/2014; 63(1):45-53. DOI:10.1538/expanim.63.45 · 1.17 Impact Factor
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    ABSTRACT: We reported recently, that the presenilin homologue signal-peptide-peptidase-like 2a (SPPL2a) is essential for B cell development by cleaving the N-terminal fragment (NTF) of the invariant chain (li, CD74). Based on this, we suggested that pharmacological modulation of SPPL2a may represent a novel approach to deplete B cells in autoimmune disorders. With regard to reported overlapping substrate spectra of SPPL2a and its close homologue SPPL2b, we have investigated the role of SPPL2b in CD74 NTF proteolysis and its impact on B and dendritic cell homeostasis. In heterologous expression experiments, SPPL2b was found to cleave CD74 NTF with similar efficiency as SPPL2a. For in vivo analysis, SPPL2b single-deficient and SPPL2a/b double-deficient mice were generated and examined for CD74 NTF turnover/accumulation, B cell maturation and functionality as well as dendritic cell homeostasis. We demonstrate that in vivo SPPL2b does not exhibit a physiologically relevant contribution to CD74 proteolysis in B and dendritic cells. Furthermore, we reveal that both proteases exhibit divergent subcellular localizations in B cells and different expression profiles in murine tissues. These findings suggest distinct functions of SPPL2a and SPPL2b and, based on a high abundance of SPPL2b in brain, a physiological role of this protease in the central nervous system.
    Molecular and Cellular Biology 02/2014; DOI:10.1128/MCB.00038-14 · 5.04 Impact Factor
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    ABSTRACT: Gene trapping in embryonic stem (ES) cells is a proven method for large-scale random insertional mutagenesis in the mouse genome. We have established an exchangeable gene trap system, in which a reporter gene can be exchanged for any other DNA of interest through Cre/mutant lox-mediated recombination. We isolated trap clones, analyzed trapped genes, and constructed the database for Exchangeable Gene Trap Clones (EGTC) [http://egtc.jp]. The number of registered ES cell lines was 1162 on 31 August 2013. We also established 454 mouse lines from trap ES clones and deposited them in the mouse embryo bank at the Center for Animal Resources and Development, Kumamoto University, Japan. The EGTC database is the most extensive academic resource for gene-trap mouse lines. Because we used a promoter-trap strategy, all trapped genes were expressed in ES cells. To understand the general characteristics of the trapped genes in the EGTC library, we used Kyoto Encyclopedia of Genes and Genomes (KEGG) for pathway analysis and found that the EGTC ES clones covered a broad range of pathways. We also used Gene Ontology (GO) classification data provided by Mouse Genome Informatics (MGI) to compare the functional distribution of genes in each GO term between trapped genes in the EGTC mouse lines and total genes annotated in MGI. We found the functional distributions for the trapped genes in the EGTC mouse lines and for the RefSeq genes for the whole mouse genome were similar, indicating that the EGTC mouse lines had trapped a wide range of mouse genes.
    Development Growth and Regeneration 01/2014; DOI:10.1111/dgd.12116 · 2.18 Impact Factor
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    ABSTRACT: Cell replacement therapy for diabetes mellitus requires cost-effective generation of high-quality, insulin-producing, pancreatic β cells from pluripotent stem cells. Development of this technique has been hampered by a lack of knowledge of the molecular mechanisms underlying β-cell differentiation. The present study identified reserpine and tetrabenazine (TBZ), both vesicular monoamine transporter 2 (VMAT2) inhibitors, as promoters of late-stage differentiation of Pdx1-positive pancreatic progenitor cells into Neurog3 (referred to henceforth as Ngn3)-positive endocrine precursors. VMAT2-controlled monoamines, such as dopamine, histamine and serotonin, negatively regulated β-cell differentiation. Reserpine or TBZ acted additively with dibutyryl adenosine 3',5'-cyclic AMP, a cell-permeable cAMP analog, to potentiate differentiation of embryonic stem (ES) cells into β cells that exhibited glucose-stimulated insulin secretion. When ES cell-derived β cells were transplanted into AKITA diabetic mice, the cells reversed hyperglycemia. Our protocol provides a basis for the understanding of β-cell differentiation and its application to a cost-effective production of functional β cells for cell therapy.
    Nature Chemical Biology 12/2013; DOI:10.1038/nchembio.1410 · 13.22 Impact Factor
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    ABSTRACT: Mouse CD99 and its paralog CD99-like 2 (CD99L2) are surface proteins implicated in cellular adhesion and migration. Although their distributions overlap in a wide variety of cells, their physical/functional relationship is currently unknown. In this study, we show the interaction between the two molecules and its consequence for membrane trafficking of mouse (m)CD99L2. The interaction was analyzed by bimolecular fluorescence complementation, immunoprecipitation, and fluorescence resonance energy transfer assays. When coexpressed, mCD99 formed heterodimers with mCD99L2, as well as homodimers, and the heterodimers were localized more efficiently at the plasma membrane than were the homodimers. Their interaction was cytoplasmic domain-dependent and enhanced mCD99L2 trafficking to the plasma membrane regardless of whether it was transiently overexpressed or endogenously expressed. Surface levels of endogenous mCD99L2 were markedly low on thymocytes, splenic leukocytes, and CTL lines derived from CD99-deficient mice. Importantly, the surface levels of mCD99L2 on mCD99-deficient cells recovered significantly when wild-type mCD99 was exogenously introduced, but they remained low when a cytoplasmic domain mutant of mCD99 was introduced. Our results demonstrate a novel role for mCD99 in membrane trafficking of mCD99L2, providing useful insights into controlling transendothelial migration of leukocytes.
    The Journal of Immunology 10/2013; 191(11). DOI:10.4049/jimmunol.1203062 · 5.36 Impact Factor
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    ABSTRACT: TASK-2 (K2P5.1) is a two-pore domain K(+) channel belonging to the TALK subgroup of the K2P family of proteins. TASK-2 has been shown to be activated by extra- and intracellular alkalinization. Extra- and intracellular pH-sensors reside at arginine 224 and lysine 245 and might affect separate selectivity filter and inner gates respectively. TASK-2 is modulated by changes in cell volume and a regulation by direct G-protein interaction has also been proposed. Activation by extracellular alkalinization has been associated with a role of TASK-2 in kidney proximal tubule bicarbonate reabsorption, whilst intracellular pH-sensitivity might be the mechanism for its participation in central chemosensitive neurons. In addition to these functions TASK-2 has been proposed to play a part in apoptotic volume decrease in kidney cells and in volume regulation of glial cells and T-lymphocytes. TASK-2 is present in chondrocytes of hyaline cartilage, where it is proposed to play a central role in stabilizing the membrane potential. Additional sites of expression are dorsal root ganglion neurons, endocrine and exocrine pancreas and intestinal smooth muscle cells. TASK-2 has been associated with the regulation of proliferation of breast cancer cells and could become target for breast cancer therapeutics. Further work in native tissues and cells together with genetic modification will no doubt reveal the details of TASK-2 functions that we are only starting to suspect.
    Frontiers in Physiology 07/2013; 4:198. DOI:10.3389/fphys.2013.00198 · 3.50 Impact Factor
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    ABSTRACT: Since the first successful reports into oocyte freezing, many papers concerning the cryopreservation of mouse oocytes have been published. However, a simple and practical cryopreservation method for unfertilized C57BL/6 mouse oocytes, and an IVF system using these cryopreserved oocytes have yet to be established, in spite of the fact that C57BL/6 is the prevalent inbred strain and is used for large-scale knockout programs. In this study, unfertilized C57BL/6 mouse oocytes were cryopreserved via a simple vitrification method. After warming, IVF was performed using cryopreserved unfertilized oocytes and fresh sperm, cryopreserved unfertilized oocytes and cold-stored sperm, cryopreserved unfertilized oocytes and frozen sperm (C57BL/6 strain sperm), and cryopreserved unfertilized oocytes and frozen sperm derived from GEM strains (C57BL/6 background GEM strains). Nearly all of the cryopreserved oocytes were recovered, of which over 90% were morphologically normal. Those oocytes were then used for in vitro fertilization, resulting in 72-97% of oocytes developing into 2-cell embryos. A portion of the 2-cell embryos were transferred to recipients, resulting in live young being produced from 32-49% of the embryos. In summary, we established the simple and practical method of mouse oocyte vitrification with high survivability and developmental ability and the IVF using the vitrified-warmed oocytes with fresh, cold-stored or cryopreserved sperm with high fertility.
    Cryobiology 07/2013; DOI:10.1016/j.cryobiol.2013.06.011 · 1.64 Impact Factor
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    ABSTRACT: Telomeres are repetitive DNA structures that, together with the shelterin and the CST complex, protect the ends of chromosomes. Telomere shortening is mitigated in stem and cancer cells through the de novo addition of telomeric repeats by telomerase. Telomere elongation requires the delivery of the telomerase complex to telomeres through a not yet fully understood mechanism. Factors promoting telomerase-telomere interaction are expected to directly bind telomeres and physically interact with the telomerase complex. In search for such a factor we carried out a SILAC-based DNA-protein interaction screen and identified HMBOX1, hereafter referred to as homeobox telomere-binding protein 1 (HOT1). HOT1 directly and specifically binds double-stranded telomere repeats, with the in vivo association correlating with binding to actively processed telomeres. Depletion and overexpression experiments classify HOT1 as a positive regulator of telomere length. Furthermore, immunoprecipitation and cell fractionation analyses show that HOT1 associates with the active telomerase complex and promotes chromatin association of telomerase. Collectively, these findings suggest that HOT1 supports telomerase-dependent telomere elongation.
    The EMBO Journal 05/2013; 32(12). DOI:10.1038/emboj.2013.105 · 10.75 Impact Factor
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    ABSTRACT: The MSM/Ms strain is derived from the Japanese wild mouse Mus musculus molossinus and displays characteristics not observed in common laboratory strains. Functional genomic analyses using genetically engineered MSM/Ms mice will reveal novel phenotypes and gene functions/interactions. We previously reported the establishment of a germline-competent embryonic stem (ES) cell line, Mol/MSM-1, from the MSM/Ms strain. To analyze its usefulness for insertional mutagenesis, we performed gene-trapping using these cells. In the present study, we compared the gene-trap events between Mol/MSM-1 and a conventional ES cell line, KTPU8, derived from the F1 progeny of a C57BL/6 × CBA cross. We introduced a promoter-trap vector carrying the promoterless β-galactosidase/neomycin-resistance fusion gene into Mol/MSM-1 and KTPU8 cells, isolated clones, and identified the trapped genes by rapid amplification of cDNA 5'-ends (5'-RACE), inverse PCR, or plasmid rescue. Unexpectedly, the success rate of 5'-RACE in Mol/MSM trap clones was 47 %, lower than the 87 % observed in KTPU8 clones. Genomic analysis of the 5'-RACE-failed clones revealed that most had trapped ribosomal RNA gene regions. The percentage of ribosomal RNA region trap clones was 41 % in Mol/MSM-1 cells, but less than 10 % in KTPU8 cells. However, within the Mol/MSM-1 5'-RACE-successful clones, the trapping frequency of annotated genes, the chromosomal distribution of vector insertions, the frequency of integration into an intron around the start codon-containing exon, and the functional spectrum of trapped genes were comparable to those in KTPU8 cells. By selecting 5'-RACE-successful clones, it is possible to perform gene-trapping efficiently using Mol/MSM-1 ES cells and promoter-trap vectors.
    Mammalian Genome 04/2013; DOI:10.1007/s00335-013-9452-4 · 2.88 Impact Factor

Publication Stats

5k Citations
609.42 Total Impact Points

Institutions

  • 1987–2015
    • Kumamoto University
      • • Institute of Resource Development and Analysis (IRDA)
      • • Department of Developmental Genetics
      • • Institute of Molecular Embryology and Genetics (IMEG)
      • • Department of Neurology
      • • Department of Cell Differentiation
      • • Gene Technology Center
      • • Department of Medical Biochemistry
      Kumamoto, Kumamoto, Japan
    • Kyushu University
      • Division of Molecular Immunology
      Hukuoka, Fukuoka, Japan
  • 2014
    • Keio University
      • Institute for Advanced Biosciences
      Edo, Tōkyō, Japan
  • 2011
    • Gwangju Institute of Science and Technology
      • Department of Life Sciences
      Gwangju, Gwangju, South Korea
  • 2002
    • University of Texas Southwestern Medical Center
      • Department of Molecular Genetics
      Dallas, Texas, United States
  • 1993–2002
    • University of Geneva
      • • Faculty of Medicine
      • • Department of Pathology and Immunology (PATIM)
      Versoix, GE, Switzerland
  • 1996
    • Harvard Medical School
      • Department of Pathology
      Boston, MA, United States
  • 1990
    • Osaka University
      • Division of Cellular and Molecular Biology
      Suika, Ōsaka, Japan
  • 1986
    • Fukushima Medical University
      • Medical Department of Pediatrics
      Hukusima, Fukushima, Japan