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Nancy A Speck - One of the best experts on this subject based on the ideXlab platform.
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RUNX1 dose dependently regulates endochondral ossification during skeletal development and fracture healing
Journal of Bone and Mineral Research, 2012Co-Authors: Do Y Soung, Laleh Talebian, Christina J Matheny, Maren E Speck, Nancy A Speck, Rosa M Guzzo, Jay R Lieberman, Hicham DrissiAbstract:RUNX1 is expressed in skeletal elements, but its role in fracture repair has not been analyzed. We created mice with a hypomorphic RUNX1 allele (RUNX1L148A) and generated RUNX1L148A/− mice in which >50% of RUNX1 activity was abrogated. RUNX1L148A/− mice were viable but runted. Their growth plates had extended proliferating and hypertrophic zones, and the percentages of Sox9, Runx2 and Runx3 positive cells were decreased. Femoral fracture experiments revealed delayed cartilaginous callus formation and the expression of chondrogenic markers was decreased. Conditional ablation of RUNX1 in the mesenchymal progenitor cells of the limb with Prx1-Cre conferred no obvious limb phenotype; however cartilaginous callus formation was delayed following fracture. Embryonic limb bud-derived mesenchymal cells showed delayed chondrogenesis when the RUNX1 allele was deleted ex vivo with adenoviral-expressed Cre. Collectively, our data suggest that RUNX1 is required for commitment and differentiation of chondroprogenitor cells into the chondrogenic lineage.
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RUNX1 deletion or dominant inhibition reduces cebpa transcription via conserved promoter and distal enhancer sites to favor monopoiesis over granulopoiesis
Blood, 2012Co-Authors: Hong Guo, Nancy A Speck, Alan D FriedmanAbstract:Deletion of RUNX1 in adult mice produces a myeloproliferative phenotype. We now find that RUNX1 gene deletion increases marrow monocyte while reducing granulocyte progenitors and that exogenous RUNX1 rescues granulopoiesis. Deletion of RUNX1 reduces Cebpa mRNA in lineage-negative marrow cells and in granulocyte-monocyte progenitors or common myeloid progenitors. Pu.1 mRNA is also decreased, but to a lesser extent. We also transduced marrow with dominant-inhibitory RUNX1a. As with RUNX1 gene deletion, RUNX1a expands lineage-Sca-1+c-kit+ and myeloid cells, increased monocyte CFUs relative to granulocyte CFUs, and reduced Cebpa mRNA. RUNX1 binds a conserved site in the Cebpa promoter and binds 4 sites in a conserved 450-bp region located at +37 kb; mutation of the enhancer sites reduces activity 6-fold in 32Dcl3 myeloid cells. Endogenous RUNX1 binds the promoter and putative +37 kb enhancer as assessed by ChIP, and RUNX1-ER rapidly induces Cebpa mRNA in these cells, even in cycloheximide, consistent with direct gene regulation. The +37 kb region contains strong H3K4me1 histone modification and p300-binding, as often seen with enhancers. Finally, exogenous C/EBPα increases granulocyte relative to monocyte progenitors in RUNX1-deleted marrow cells. Diminished CEBPA transcription and consequent impairment of myeloid differentiation may contribute to leukemic transformation in acute myeloid leukemia cases associated with decreased RUNX1 activity.
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A Hypomorphic Cbfb Allele Reveals a Critical Dosage-Sensitive Function of Core Binding Factors at the Earliest Stages of T Cell Development.
Blood, 2005Co-Authors: Ivan Maillard, Laleh Talebian, Maren E Speck, Warren S Pear, Zhe Li, Daisuke Sugiyama, Nancy A SpeckAbstract:The family of core binding factors includes the DNA-binding subunits RUNX1-3 and the common non-DNA binding partner CBFβ. RUNX1 and CBFβ are essential for the emergence of hematopoietic stem cells during fetal development, but not for stem cell maintenance during later ontogeny. RUNX1 is also required for megakaryocyte differentiation, B cell development, and for the DN2 to DN3 transition in thymocyte development. Runx2/CBFβ are critical for normal osteogenesis, and Runx3 for CD4 silencing in CD8+ T cells, but their contribution to other steps of hematopoietic development is unknown. To examine the collective role of core binding factors in hematopoiesis, we generated a hypomorphic Cbfb allele ( Cbfb rss). CBFβ protein levels were reduced by approximately 2–3 fold in fetuses homozygous for the Cbfb rss allele ( Cbfb rss/rss), and 3–4 fold in fetuses carrying one hypomorphic and one knockout allele ( Cbfb rss/−). Cbfb rss/rss and Cbfb rss/− fetuses had normal erythroid and B cell development, and relatively mild abnormalities in megakaryocyte and granulocyte differentiation. In contrast, T cell development was very sensitive to an incremental reduction of CBFβ levels: mature thymocytes were decreased in Cbfb rss/rss fetuses, and virtually absent in Cbfb rss/−fetuses. We next assessed the development of Cbfb rss/rss and Cbfb rss/− fetal liver progenitors after transplantation to irradiated adult recipients, in competition with wild-type ( wt ) bone marrow cells. Wt , Cbfb rss/rss and Cbfb rss/− fetal progenitors replenished the erythroid, myeloid and B cell compartments equally well. The overall development of Cbfb rss/rss T cells was preserved, although CD4 expression was derepressed in double negative thymocytes. In Cbfb rss/− chimeras, mature thymocytes were entirely derived from competitor cells. Furthermore, the developmental block in Cbfb rss/− progenitors was present at the earliest stages of T cell development within the DN1 (ETP) and DN2 subsets. Our data define a critical CBFβ threshold for normal T cell development, and they situate an essential role of core binding factors during the earliest stages of T cell development. In addition, early thymopoiesis appeared more severely affected by reduced CBFβ dosage than by the lack of RUNX1 (Ichikawa et al. , Nat Med 2004; Growney et al. , Blood 2005), suggesting that Runx2/3 may contribute to core binding factor activity in the T cell lineage.
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the cbfb smmhc oncoprotein inhibits binding of the RUNX1 runt domain to dna
Blood, 2005Co-Authors: John H Bushweller, Stephen M Lukasik, Nancy A SpeckAbstract:Core-binding factors (CBFs) are heterodimeric transcriptional factors consisting of a DNA-binding RUNX1 (CBFα) subunit and a CBFβ subunit. Cbfβ allosterically increases the affinity of RUNX1 for DNA ~2.5 fold. CBF subunits are encoded by four genes in mammals. RUNX1 (AML1), RUNX2, and RUNX3 encode for CBFα subunits, and CBFB encodes the CBFβ subunit. Homozygous disruption of either the RUNX1 or the Cbfb genes in mice results in essentially identical phenotypes: midgestation embryonic lethality accompanied by extensive hemorrhaging and a profound block at the fetal liver stage of hematopoiesis. In humans, chromosomal rearrangements that disrupt the RUNX1 and CBFB genes are associated with a significant percentage of leukemias. CBFβ is disrupted in acute myeloid leukemia by inv(16)(p13;q22), t(16;16), and del(16)(q22). These translocations result in the production of novel fusion proteins containing most of the CBFβ protein fused to the C-terminal coiled-coil domain from smooth muscle myosin heavy chain (SMMHC) encoded by the MYH11 gene. A knock-in of the CBFB-MYH11 allele in mice resulted in embryonic lethality with a profound block in hematopoietic development, the same phenotype observed for the RUNX1 and Cbfb knockouts. We recently demonstrated that the CBFβ-SMMHC fusion protein binds to the DNA binding Runt domain from RUNX1 with both higher affinity and altered stoichiometry relative to native CBFβ. We also provided NMR-based evidence for multiple sites of contact between RUNX1 and CBFβ-SMMHC, proving the role of the SMMHC sequence in creating this altered affinity. Here we demonstrate that CBFβ-SMMHC inhibits DNA binding of the RUNX1 Runt domain by ~6-fold for the CD4 dual-site silencer element. Cross-saturation NMR mapping on the Runt domain in complex with CBFβ-SMMHC reveals that the SMMHC portion of the oncoprotein makes contacts with β-strands 1 and 2 in the Runt domain. We propose that the inhibition of DNA-binding and increased affinity combine to mediate the dysregulation of Runx-regulated genes caused by CBFβ-SMMHC. These results also clearly suggest that targeting of the CBFβ-SMMHC protein for drug development may well be a viable approach for the treatment of the associated leukemia.
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biochemical and in vivo characterization of amino acid substitutions in the RUNX1 aml1 runt domain found in fpd aml aml m0 and cleidocranial dysplasia ccd patients
Blood, 2004Co-Authors: Christina J Matheny, Takeshi Corpora, Maren E Speck, Tinglei Gu, John H Bushweller, Nancy A SpeckAbstract:RUNX1 and CBF β are the DNA-binding and non DNA-binding subunits of a core-binding factor that is required for hematopoiesis, and that is frequently mutated in leukemia. Runx2 is the DNA-binding subunit of a core-binding factor required for bone formation. Mono-allelic deletion, nonsense, frameshift, and missense mutations have been found in RUNX1 in familial platelet disorder with predisposition for acute myelogenous leukemia (FPD/AML) and in myelodysplastic syndrome (MDS), and biallelic mutations in RUNX1 are found in 20% of AML M0 patients. Similar types of mono-allelic mutations have been found in RUNX2 in patients with cleidocranial dysplasia (CCD), an inherited skeletal syndrome. FPD/AML and CCD pedigrees have revealed varying degrees of disease severity depending on the nature of the specific mutation. Additionally, it has been observed that mutations involving amino acids in the DNA binding Runt domain that directly contact DNA are associated primarily with RUNX1 and hematopoietic disorders, while mutations predicted to disrupt CBF β binding or the Runt domain structure are found only in Runx2 in CCD patients. We introduced 21 amino acid substitutions into the Runt domain of RUNX1 identified in FPD/AML, AML M0, and CCD patients, and quantified their effects on DNA binding, heterodimerization with CBFβ, and the Runt domain structure using yeast one- and two-hybrid, quantitative electrophoretic mobility shift, heteronuclear single quantum correlation spectroscopy, and urea denaturation experiments. To address the impact on in vivo function, several of these point mutations were engineered into the endogenous RUNX1 allele in mice. These five mutations include: R177X, R174Q, T149A, T161A, and L148F. R177X is found in FPD/AML patients and truncates RUNX1 two amino acids before the C-terminal boundary of the Runt domain. R174Q (found in FPD/AML and CCD) disrupts DNA binding 1000-fold, but does not disrupt CBFb binding or perturb the Runt domain fold. T149A (found only in CCD) disrupts CBFβ binding 13-fold while T161A (not found in patients) disrupts CBFβ binding 40-fold. Both T149A and T161A slightly perturb the Runt domain fold, but do not alter DNA binding affinity. L148F (found in CCD) also disrupts the Runt domain fold, and decreases DNA binding. All animals heterozygous for these alleles are viable. Mice homozygous for R177X and R174Q die during gestation. Mice homozygous for the T149A and T161A mutations, on the other hand, are born at normal Mendelian frequencies, but 62% and 100%, respectively, die by or at three weeks of age from an undetermined cause. The effects of these mutations on hematopoietic progenitor and platelet numbers, both of which are affected in FPD/AML patients, will be presented. We conclude that mutations that affect CBFβ binding result in hypomorphic RUNX1 alleles, while mutations involving DNA contacts result in more severe inactivation of RUNX1 function. Thus FPD/AML, AML M0, and MDS require mutations that severely inactivate RUNX1 function, while CCD can result from more subtle alterations in Runx2.
Shari Meyers - One of the best experts on this subject based on the ideXlab platform.
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RUNX1 aml 1 and runx2 aml 3 cooperate with prostate derived ets factor to activate transcription from the psa upstream regulatory region
Journal of Cellular Biochemistry, 2006Co-Authors: Marcie Fowler, Erkut Borazanci, Laura L Mcghee, Shannon Walls Pylant, Jill B Williams, Jonathan D Glass, Nathan J Davis, Shari MeyersAbstract:The RUNX transcription factors (RUNX1, RUNX2, and RUNX3) play essential roles in hematopoiesis and skeletal development. Consistent with these roles in differentiation and cell cycle, the activity of both RUNX1 and RUNX3 is perturbed in cancer. To determine a role for the RUNX factors in prostate biology, we investigated the expression of RUNX factors in prostate epithelial cell lines and normal prostate tissue. RUNX1, RUNX2, and RUNX3 were expressed in both normal prostate tissue and an immortalized, non-transformed cell line. We found that prostate cancer-derived cell lines expressed RUNX1 and RUNX2, but not RUNX3. Next, we sought to identify prostate-specific genes whose expression could be regulated by RUNX proteins. Four consensus RUNX sites are located within the prostate-specific antigen (PSA) regulatory region. Chromatin immunoprecipitation (ChIP) analysis showed that RUNX1 is specifically bound to the PSA regulatory region in LNCaP cells. RUNX1 and RUNX2 activated the PSA regulatory region alone or cooperatively with prostate-derived ETS factor (PDEF) and RUNX1 physically associated with PDEF. Taken together, our results suggest that RUNX factors participate in prostate epithelial cell function and cooperate with an Ets transcription factor to regulate PSA gene expression.
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RUNX1 aml 1 and runx2 aml 3 cooperate with prostate derived ets factor to activate transcription from the psa upstream regulatory region
Journal of Cellular Biochemistry, 2006Co-Authors: Marcie Fowler, Erkut Borazanci, Laura L Mcghee, Shannon Walls Pylant, Jill B Williams, Nathan J Davis, Shari Meyers, Jonathan GlassAbstract:The RUNX transcription factors (RUNX1, RUNX2, and RUNX3) play essential roles in hematopoiesis and skeletal development. Consistent with these roles in differentiation and cell cycle, the activity of both RUNX1 and RUNX3 is perturbed in cancer. To determine a role for the RUNX factors in prostate biology, we investigated the expression of RUNX factors in prostate epithelial cell lines and normal prostate tissue. RUNX1, RUNX2, and RUNX3 were expressed in both normal prostate tissue and an immortalized, non-transformed cell line. We found that prostate cancer-derived cell lines expressed RUNX1 and RUNX2, but not RUNX3. Next, we sought to identify prostate-specific genes whose expression could be regulated by RUNX proteins. Four consensus RUNX sites are located within the prostate-specific antigen (PSA) regulatory region. Chromatin immunoprecipitation (ChIP) analysis showed that RUNX1 is specifically bound to the PSA regulatory region in LNCaP cells. RUNX1 and RUNX2 activated the PSA regulatory region alone or cooperatively with prostate-derived ETS factor (PDEF) and RUNX1 physically associated with PDEF. Taken together, our results suggest that RUNX factors participate in prostate epithelial cell function and cooperate with an Ets transcription factor to regulate PSA gene expression. J. Cell. Biochem. © 2005 Wiley-Liss, Inc.
Motomi Osato - One of the best experts on this subject based on the ideXlab platform.
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Runx Family Genes in a Cartilaginous Fish, the Elephant Shark (Callorhinchus milii)
2016Co-Authors: Giselle Sek, Boonhui Tay, Zhi Wei Lim, Suan Nah, Motomi OsatoAbstract:The Runx family genes encode transcription factors that play key roles in hematopoiesis, skeletogenesis and neurogenesis and are often implicated in diseases. We describe here the cloning and characterization of RUNX1, Runx2, Runx3 and Runxb genes in the elephant shark (Callorhinchus milii), a member of Chondrichthyes, the oldest living group of jawed vertebrates. Through the use of alternative promoters and/or alternative splicing, each of the elephant shark Runx genes expresses multiple isoforms similar to their orthologs in human and other bony vertebrates. The expression profiles of elephant shark Runx genes are similar to those of mammalian Runx genes. The syntenic blocks of genes at the elephant shark Runx gene loci are highly conserved in human, but represented by shorter conserved blocks in zebrafish indicating a higher degree of rearrangements in this teleost fish. Analysis of promoter regions revealed conservation of binding sites for transcription factors, including two tandem binding sites for Runx that are totally conserved in the distal promoter regions of elephant shark RUNX1-3. Several conserved noncoding elements (CNEs), which are putative cis-regulatory elements, and miRNA binding sites were identified in the elephant shark and human Runx gene loci. Some of these CNEs and miRNA binding sites are absent in teleost fishes such as zebrafish and fugu. In summary, our analysis reveals that the genomic organization an
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Characterization of the Runx Gene Family in a Jawless Vertebrate, the Japanese Lamprey (Lethenteron japonicum)
2016Co-Authors: Giselle Sek, Boonhui Tay, Sydney Brenner, Suan Nah, Motomi OsatoAbstract:The cyclostomes (jawless vertebrates), comprising lampreys and hagfishes, are the sister group of jawed vertebrates (gnathostomes) and are hence an important group for the study of vertebrate evolution. In mammals, three Runx genes, RUNX1, Runx2 and Runx3, encode transcription factors that are essential for cell proliferation and differentiation in major developmental pathways such as haematopoiesis, skeletogenesis and neurogenesis and are frequently associated with diseases. We describe here the characterization of Runx gene family members from a cyclostome, the Japanese lamprey (Lethenteron japonicum). The Japanese lamprey contains three Runx genes, RunxA, RunxB, and RunxC. However, phylogenetic and synteny analyses suggest that they are not one-to-one orthologs of gnathostome RUNX1, Runx2 and Runx3. The major protein domains and motifs found in gnathostome Runx proteins are highly conserved in the lamprey Runx proteins. Although all gnathostome Runx genes each contain two alternative promoters, P1 (distal) and P2 (proximal), only lamprey RunxB possesses the alternative promoters; lamprey RunxA and RunxC contain only P2 and P1 promoter, respectively. Furthermore, the three lamprey Runx genes give rise to fewer alternative isoforms than the three gnathostome Runx genes. The promoters of the lamprey Runx genes lack the tandem Runx-binding motifs that are highly conserved among the P1 promoters of gnathostome RUNX1, Runx2 and Runx3 genes; instead these promoters contain dispersed single Runx-binding motifs. The 39UTR of lamprey RunxB contains binding sites for miR-27 and miR-130b/301ab, which ar
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characterization of the runx gene family in a jawless vertebrate the japanese lamprey lethenteron japonicum
PLOS ONE, 2014Co-Authors: Giselle Sek Suan Nah, Motomi Osato, Sydney Brenner, Boonhui Tay, Byrappa VenkateshAbstract:The cyclostomes (jawless vertebrates), comprising lampreys and hagfishes, are the sister group of jawed vertebrates (gnathostomes) and are hence an important group for the study of vertebrate evolution. In mammals, three Runx genes, RUNX1, Runx2 and Runx3, encode transcription factors that are essential for cell proliferation and differentiation in major developmental pathways such as haematopoiesis, skeletogenesis and neurogenesis and are frequently associated with diseases. We describe here the characterization of Runx gene family members from a cyclostome, the Japanese lamprey (Lethenteron japonicum). The Japanese lamprey contains three Runx genes, RunxA, RunxB, and RunxC. However, phylogenetic and synteny analyses suggest that they are not one-to-one orthologs of gnathostome RUNX1, Runx2 and Runx3. The major protein domains and motifs found in gnathostome Runx proteins are highly conserved in the lamprey Runx proteins. Although all gnathostome Runx genes each contain two alternative promoters, P1 (distal) and P2 (proximal), only lamprey RunxB possesses the alternative promoters; lamprey RunxA and RunxC contain only P2 and P1 promoter, respectively. Furthermore, the three lamprey Runx genes give rise to fewer alternative isoforms than the three gnathostome Runx genes. The promoters of the lamprey Runx genes lack the tandem Runx-binding motifs that are highly conserved among the P1 promoters of gnathostome RUNX1, Runx2 and Runx3 genes; instead these promoters contain dispersed single Runx-binding motifs. The 3′UTR of lamprey RunxB contains binding sites for miR-27 and miR-130b/301ab, which are conserved in mammalian RUNX1 and Runx3, respectively. Overall, the Runx genes in lamprey seem to have experienced a different evolutionary trajectory from that of gnathostome Runx genes which are highly conserved all the way from cartilaginous fishes to mammals.
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runx family genes in a cartilaginous fish the elephant shark callorhinchus milii
PLOS ONE, 2014Co-Authors: Giselle Sek Suan Nah, Motomi Osato, Zhi Wei Lim, Boonhui Tay, Byrappa VenkateshAbstract:The Runx family genes encode transcription factors that play key roles in hematopoiesis, skeletogenesis and neurogenesis and are often implicated in diseases. We describe here the cloning and characterization of RUNX1, Runx2, Runx3 and Runxb genes in the elephant shark (Callorhinchus milii), a member of Chondrichthyes, the oldest living group of jawed vertebrates. Through the use of alternative promoters and/or alternative splicing, each of the elephant shark Runx genes expresses multiple isoforms similar to their orthologs in human and other bony vertebrates. The expression profiles of elephant shark Runx genes are similar to those of mammalian Runx genes. The syntenic blocks of genes at the elephant shark Runx gene loci are highly conserved in human, but represented by shorter conserved blocks in zebrafish indicating a higher degree of rearrangements in this teleost fish. Analysis of promoter regions revealed conservation of binding sites for transcription factors, including two tandem binding sites for Runx that are totally conserved in the distal promoter regions of elephant shark RUNX1-3. Several conserved noncoding elements (CNEs), which are putative cis-regulatory elements, and miRNA binding sites were identified in the elephant shark and human Runx gene loci. Some of these CNEs and miRNA binding sites are absent in teleost fishes such as zebrafish and fugu. In summary, our analysis reveals that the genomic organization and expression profiles of Runx genes were already complex in the common ancestor of jawed vertebrates.
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Conserved noncoding elements (CNEs) in Runx loci.
2014Co-Authors: Giselle Sek Suan Nah, Motomi Osato, Zhi Wei Lim, Boonhui Tay, Byrappa VenkateshAbstract:VISTA plots obtained from the global alignment between the human, mouse, dog, opossum, chicken, lizard, frog, zebrafish, fugu and elephant shark (A) RUNX1, (B) Runx2 and (C) Runx3 loci are shown. Sequence for opossum Runx2 locus is not available. Human sequence is used as the reference sequence. Conserved sequences were predicted at a cut-off of ≥65% identity across >50 bp windows and are represented by peaks. Blue peaks denote conserved coding exons, pink peaks conserved noncoding regions (CNRs) and cyan peaks untranslated regions (UTRs). Experimentally verified CNEs (mm657 and mm924) in the Runx2 locus are indicated with blue arrows below the x-axis and labelled.
Ichiro Taniuchi - One of the best experts on this subject based on the ideXlab platform.
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core binding factors are essential for ovulation luteinization and female fertility in mice
Scientific Reports, 2020Co-Authors: Somang Leethacker, Ichiro Taniuchi, Hayce Jeon, Yohan Choi, Takeshi Takarada, Yukio Yoneda, Chemyong Ko, Misung JoAbstract:Core Binding Factors (CBFs) are a small group of heterodimeric transcription factor complexes composed of DNA binding proteins, RUNXs, and a non-DNA binding protein, CBFB. The LH surge increases the expression of RUNX1 and Runx2 in ovulatory follicles, while Cbfb is constitutively expressed. To investigate the physiological significance of CBFs, we generated a conditional mutant mouse model in which granulosa cell expression of Runx2 and Cbfb was deleted by the Esr2Cre. Female Cbfbflox/flox;Esr2cre/+;Runx2flox/flox mice were infertile; follicles developed to the preovulatory follicle stage but failed to ovulate. RNA-seq analysis of mutant mouse ovaries collected at 11 h post-hCG unveiled numerous CBFs-downstream genes that are associated with inflammation, matrix remodeling, wnt signaling, and steroid metabolism. Mutant mice also failed to develop corpora lutea, as evident by the lack of luteal marker gene expression, marked reduction of vascularization, and excessive apoptotic staining in unruptured poorly luteinized follicles, consistent with dramatic reduction of progesterone by 24 h after hCG administration. The present study provides in vivo evidence that CBFs act as essential transcriptional regulators of both ovulation and luteinization by regulating the expression of key genes that are involved in inflammation, matrix remodeling, cell differentiation, vascularization, and steroid metabolisms in mice.
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Core Binding Factors are essential for ovulation, luteinization, and female fertility in mice
'Springer Science and Business Media LLC', 2020Co-Authors: Somang Lee-thacker, Ichiro Taniuchi, Hayce Jeon, Yohan Choi, Takeshi Takarada, Yukio YonedaAbstract:Abstract Core Binding Factors (CBFs) are a small group of heterodimeric transcription factor complexes composed of DNA binding proteins, RUNXs, and a non-DNA binding protein, CBFB. The LH surge increases the expression of RUNX1 and Runx2 in ovulatory follicles, while Cbfb is constitutively expressed. To investigate the physiological significance of CBFs, we generated a conditional mutant mouse model in which granulosa cell expression of Runx2 and Cbfb was deleted by the Esr2Cre. Female Cbfb flox/flox ;Esr2 cre/+ ;Runx2 flox/flox mice were infertile; follicles developed to the preovulatory follicle stage but failed to ovulate. RNA-seq analysis of mutant mouse ovaries collected at 11 h post-hCG unveiled numerous CBFs-downstream genes that are associated with inflammation, matrix remodeling, wnt signaling, and steroid metabolism. Mutant mice also failed to develop corpora lutea, as evident by the lack of luteal marker gene expression, marked reduction of vascularization, and excessive apoptotic staining in unruptured poorly luteinized follicles, consistent with dramatic reduction of progesterone by 24 h after hCG administration. The present study provides in vivo evidence that CBFs act as essential transcriptional regulators of both ovulation and luteinization by regulating the expression of key genes that are involved in inflammation, matrix remodeling, cell differentiation, vascularization, and steroid metabolisms in mice
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core binding factor β expression in ovarian granulosa cells is essential for female fertility
Endocrinology, 2018Co-Authors: Somang Leethacker, Ichiro Taniuchi, Yohan Choi, Takeshi Takarada, Yukio YonedaAbstract:Core binding factor β (CBFβ) is a non-DNA-binding partner of all RUNX proteins and critical for transcription activity of CBF transcription factors (RUNXs/CBFβ). In the ovary, the expression of RUNX1 and Runx2 is highly induced by the luteinizing hormone (LH) surge in ovulatory follicles, whereas Cbfb is constitutively expressed. To investigate the physiological significance of CBFs in the ovary, the current study generated two different conditional mutant mouse models in which granulosa cell expression of Cbfb and Runx2 was reduced by Cre recombinase driven by an Esr2 promoter. Cbfbgc-/- and Cbfbgc-/- × Runx2gc+/- mice exhibited severe subfertility and infertility, respectively. In the ovaries of both mutant mice, follicles develop normally, but the majority of preovulatory follicles failed to ovulate either in response to human chorionic gonadotropin administration in pregnant mare serum gonadotropin-primed immature animals or after the LH surge at 5 months of age. Morphological and physiological changes in the corpus luteum of these mutant mice revealed the reduced size, progesterone production, and vascularization, as well as excessive lipid accumulation. In granulosa cells of periovulatory follicles and corpora lutea of these mice, the expression of Edn2, Ptgs1, Lhcgr, Sfrp4, Wnt4, Ccrl2, Lipg, Saa3, and Ptgfr was also drastically reduced. In conclusion, the current study provided in vivo evidence that CBFβ plays an essential role in female fertility by acting as a critical cofactor of CBF transcription factor complexes, which regulate the expression of specific key ovulatory and luteal genes, thus coordinating the ovulatory process and luteal development/function in mice.
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central role of core binding factor β2 in mucosa associated lymphoid tissue organogenesis in mouse
PLOS ONE, 2015Co-Authors: Takahiro Nagatake, Ichiro Taniuchi, Satoshi Fukuyama, Shintaro Sato, Hideaki Okura, Masashi Tachibana, Kosei Ito, Michiko Shimojou, Naomi Matsumoto, Hidehiko SuzukiAbstract:Mucosa-associated lymphoid tissue (MALT) is a group of secondary and organized lymphoid tissue that develops at different mucosal surfaces. Peyer’s patches (PPs), nasopharynx-associated lymphoid tissue (NALT), and tear duct-associated lymphoid tissue (TALT) are representative MALT in the small intestine, nasal cavity, and lacrimal sac, respectively. A recent study has shown that transcriptional regulators of core binding factor (Cbf) β2 and promotor-1-transcribed Runt-related transcription factor 1 (P1-RUNX1) are required for the differentiation of CD3−CD4+CD45+ lymphoid tissue inducer (LTi) cells, which initiate and trigger the developmental program of PPs, but the involvement of this pathway in NALT and TALT development remains to be elucidated. Here we report that Cbfβ2 plays an essential role in NALT and TALT development by regulating LTi cell trafficking to the NALT and TALT anlagens. Cbfβ2 was expressed in LTi cells in all three types of MALT examined. Indeed, similar to the previous finding for PPs, we found that Cbfβ2−/− mice lacked NALT and TALT lymphoid structures. However, in contrast to PPs, NALT and TALT developed normally in the absence of P1-RUNX1 or other Runx family members such as Runx2 and Runx3. LTi cells for NALT and TALT differentiated normally but did not accumulate in the respective lymphoid tissue anlagens in Cbfβ2−/− mice. These findings demonstrate that Cbfβ2 is a central regulator of the MALT developmental program, but the dependency of Runx proteins on the lymphoid tissue development would differ among PPs, NALT, and TALT.
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cbfb regulates bone development by stabilizing runx family proteins
Journal of Bone and Mineral Research, 2015Co-Authors: Xin Qin, Ichiro Taniuchi, Kosei Ito, Qing Jiang, Yuki Matsuo, Tetsuya Kawane, Hisato Komori, Takeshi Moriishi, Yosuke Kawai, Satoshi RokutandaAbstract:Runx family proteins, RUNX1, Runx2, and Runx3, play important roles in skeletal development. Runx2 is required for osteoblast differentiation and chondrocyte maturation, and haplodeficiency of RUNX2 causes cleidocranial dysplasia, which is characterized by open fontanelles and sutures and hypoplastic clavicles. Cbfb forms a heterodimer with Runx family proteins and enhances their DNA-binding capacity. Cbfb-deficient (Cbfb(-/-) ) mice die at midgestation because of the lack of fetal liver hematopoiesis. We previously reported that the partial rescue of hematopoiesis in Cbfb(-/-) mice revealed the requirement of Cbfb in skeletal development. However, the precise functions of Cbfb in skeletal development still remain to be clarified. We deleted Cbfb in mesenchymal cells giving rise to both chondrocyte and osteoblast lineages by mating Cbfb(fl/fl) mice with Dermo1 Cre knock-in mice. Cbfb(fl/fl/Cre) mice showed dwarfism, both intramembranous and endochondral ossifications were retarded, and chondrocyte maturation and proliferation and osteoblast differentiation were inhibited. The differentiation of chondrocytes and osteoblasts were severely inhibited in vitro, and the reporter activities of Ihh, Col10a1, and Bglap2 promoter constructs were reduced in Cbfb(fl/fl/Cre) chondrocytes or osteoblasts. The proteins of RUNX1, Runx2, and Runx3 were reduced in the cartilaginous limb skeletons and calvariae of Cbfb(fl/fl/Cre) embryos compared with the respective protein in the respective tissue of Cbfb(fl/fl) embryos at E15.5, although the reduction of Runx2 protein in calvariae was much milder than that in cartilaginous limb skeletons. All of the Runx family proteins were severely reduced in Cbfb(fl/fl/Cre) primary osteoblasts, and Runx2 protein was less stable in Cbfb(fl/fl/Cre) osteoblasts than Cbfb(fl/fl) osteoblasts. These findings indicate that Cbfb is required for skeletal development by regulating chondrocyte differentiation and proliferation and osteoblast differentiation; that Cbfb plays an important role in the stabilization of Runx family proteins; and that Runx2 protein stability is less dependent on Cbfb in calvariae than in cartilaginous limb skeletons.
Giselle Sek Suan Nah - One of the best experts on this subject based on the ideXlab platform.
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characterization of the runx gene family in a jawless vertebrate the japanese lamprey lethenteron japonicum
PLOS ONE, 2014Co-Authors: Giselle Sek Suan Nah, Motomi Osato, Sydney Brenner, Boonhui Tay, Byrappa VenkateshAbstract:The cyclostomes (jawless vertebrates), comprising lampreys and hagfishes, are the sister group of jawed vertebrates (gnathostomes) and are hence an important group for the study of vertebrate evolution. In mammals, three Runx genes, RUNX1, Runx2 and Runx3, encode transcription factors that are essential for cell proliferation and differentiation in major developmental pathways such as haematopoiesis, skeletogenesis and neurogenesis and are frequently associated with diseases. We describe here the characterization of Runx gene family members from a cyclostome, the Japanese lamprey (Lethenteron japonicum). The Japanese lamprey contains three Runx genes, RunxA, RunxB, and RunxC. However, phylogenetic and synteny analyses suggest that they are not one-to-one orthologs of gnathostome RUNX1, Runx2 and Runx3. The major protein domains and motifs found in gnathostome Runx proteins are highly conserved in the lamprey Runx proteins. Although all gnathostome Runx genes each contain two alternative promoters, P1 (distal) and P2 (proximal), only lamprey RunxB possesses the alternative promoters; lamprey RunxA and RunxC contain only P2 and P1 promoter, respectively. Furthermore, the three lamprey Runx genes give rise to fewer alternative isoforms than the three gnathostome Runx genes. The promoters of the lamprey Runx genes lack the tandem Runx-binding motifs that are highly conserved among the P1 promoters of gnathostome RUNX1, Runx2 and Runx3 genes; instead these promoters contain dispersed single Runx-binding motifs. The 3′UTR of lamprey RunxB contains binding sites for miR-27 and miR-130b/301ab, which are conserved in mammalian RUNX1 and Runx3, respectively. Overall, the Runx genes in lamprey seem to have experienced a different evolutionary trajectory from that of gnathostome Runx genes which are highly conserved all the way from cartilaginous fishes to mammals.
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disruption of RUNX1 and runx3 leads to bone marrow failure and leukemia predisposition due to transcriptional and dna repair defects
Cell Reports, 2014Co-Authors: Chelsia Qiuxia Wang, Lavina Sierra Tay, Vaidehi Krishnan, Giselle Sek Suan Nah, Desmond Wai Loon Chin, Cai Ping Koh, Jing Yuan Chooi, Bindya JacobAbstract:The RUNX genes encode transcription factors involved in development and human disease. RUNX1 and RUNX3 are frequently associated with leukemias, yet the basis for their involvement in leukemogenesis is not fully understood. Here, we show that RUNX1;Runx3 double-knockout (DKO) mice exhibited lethal phenotypes due to bone marrow failure and myeloproliferative disorder. These contradictory clinical manifestations are reminiscent of human inherited bone marrow failure syndromes such as Fanconi anemia (FA), caused by defective DNA repair. Indeed, RUNX1;Runx3 DKO cells showed mitomycin C hypersensitivity, due to impairment of monoubiquitinated-FANCD2 recruitment to DNA damage foci, although FANCD2 monoubiquitination in the FA pathway was unaffected. RUNX1 and RUNX3 interact with FANCD2 independently of CBFβ, suggesting a nontranscriptional role for RUNX in DNA repair. These findings suggest that RUNX dysfunction causes DNA repair defect, besides transcriptional misregulation, and promotes the development of leukemias and other cancers.
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runx family genes in a cartilaginous fish the elephant shark callorhinchus milii
PLOS ONE, 2014Co-Authors: Giselle Sek Suan Nah, Motomi Osato, Zhi Wei Lim, Boonhui Tay, Byrappa VenkateshAbstract:The Runx family genes encode transcription factors that play key roles in hematopoiesis, skeletogenesis and neurogenesis and are often implicated in diseases. We describe here the cloning and characterization of RUNX1, Runx2, Runx3 and Runxb genes in the elephant shark (Callorhinchus milii), a member of Chondrichthyes, the oldest living group of jawed vertebrates. Through the use of alternative promoters and/or alternative splicing, each of the elephant shark Runx genes expresses multiple isoforms similar to their orthologs in human and other bony vertebrates. The expression profiles of elephant shark Runx genes are similar to those of mammalian Runx genes. The syntenic blocks of genes at the elephant shark Runx gene loci are highly conserved in human, but represented by shorter conserved blocks in zebrafish indicating a higher degree of rearrangements in this teleost fish. Analysis of promoter regions revealed conservation of binding sites for transcription factors, including two tandem binding sites for Runx that are totally conserved in the distal promoter regions of elephant shark RUNX1-3. Several conserved noncoding elements (CNEs), which are putative cis-regulatory elements, and miRNA binding sites were identified in the elephant shark and human Runx gene loci. Some of these CNEs and miRNA binding sites are absent in teleost fishes such as zebrafish and fugu. In summary, our analysis reveals that the genomic organization and expression profiles of Runx genes were already complex in the common ancestor of jawed vertebrates.
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Conserved noncoding elements (CNEs) in Runx loci.
2014Co-Authors: Giselle Sek Suan Nah, Motomi Osato, Zhi Wei Lim, Boonhui Tay, Byrappa VenkateshAbstract:VISTA plots obtained from the global alignment between the human, mouse, dog, opossum, chicken, lizard, frog, zebrafish, fugu and elephant shark (A) RUNX1, (B) Runx2 and (C) Runx3 loci are shown. Sequence for opossum Runx2 locus is not available. Human sequence is used as the reference sequence. Conserved sequences were predicted at a cut-off of ≥65% identity across >50 bp windows and are represented by peaks. Blue peaks denote conserved coding exons, pink peaks conserved noncoding regions (CNRs) and cyan peaks untranslated regions (UTRs). Experimentally verified CNEs (mm657 and mm924) in the Runx2 locus are indicated with blue arrows below the x-axis and labelled.
