scholarly journals Excessive Reactive Iron Impairs Hematopoiesis by Affecting Both Immature Hematopoietic Cells and Stromal Cells

Cells ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 226 ◽  
Author(s):  
Hirokazu Tanaka ◽  
J. Espinoza ◽  
Ryosuke Fujiwara ◽  
Shinya Rai ◽  
Yasuyoshi Morita ◽  
...  
Keyword(s):  
Iron Overload ◽  
Stromal Cells ◽  
Es Cells ◽  
Genetic Disorders ◽  
Hematopoietic Cells ◽  
Embryonic Stem ◽  
The Body ◽  
Ferrous Ammonium Sulfate ◽  
Excess Iron

Iron overload is the accumulation of excess iron in the body that may occur as a result of various genetic disorders or as a consequence of repeated blood transfusions. The surplus iron is then stored in the liver, pancreas, heart and other organs, which may lead to chronic liver disease or cirrhosis, diabetes and heart disease, respectively. In addition, excessive iron may impair hematopoiesis, although the mechanisms of this deleterious effect is not entirely known. In this study, we found that ferrous ammonium sulfate (FeAS), induced growth arrest and apoptosis in immature hematopoietic cells, which was mediated via reactive oxygen species (ROS) activation of p38MAPK and JNK pathways. In in vitro hematopoiesis derived from embryonic stem cells (ES cells), FeAS enhanced the development of dysplastic erythroblasts but inhibited their terminal differentiation; in contrast, it had little effect on the development of granulocytes, megakaryocytes, and B lymphocytes. In addition to its directs effects on hematopoietic cells, iron overload altered the expression of several adhesion molecules on stromal cells and impaired the cytokine production profile of these cells. Therefore, excessive iron would affect whole hematopoiesis by inflicting vicious effects on both immature hematopoietic cells and stromal cells.

Bonr Marrow Reconstitution from Mouse Embryonic Stem Cell-Derived Hematopoietic Cells.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4145-4145
Author(s):  
Momoko Yoshimoto ◽  
Chang Hsi ◽  
Katsutsugu Umeda ◽  
Midori Iida ◽  
Toshio Heike ◽  
...  
Keyword(s):  
Stromal Cells ◽  
Stromal Cell ◽  
Es Cells ◽  
Hematopoietic Cells ◽  
Embryonic Stem ◽  
Scid Mice ◽  
Pcr Analysis ◽  
Facs Analysis ◽  
Cd34 Cells

Abstract Differentiation of embryonic stem (ES) cells in vitro yield different kinds of hematopoietic progenitors including primitive and definitive hematopoietic cells. It has been reported that HOXB4 induction enable york sac (YS) cells and embryoid body-derived cells to engraft in the irradiated adult mice, however, since the characteristic of ES-derived transplantable cells is not clear, generating hematopoietic stem cells (HSCs) in vitro still remains to be resolved. We previously reported the generation of definitive HSCs from both early YS and intraembryonic paraaortic splanchnopleures (P-Sp) on AGM-S3 stromal cells derived from the aorta-gonad-mesonephros (AGM) region at 10.5 days post coitum (Matsuoka, et al; Blood 2001) Co-cultureing on AGM-S3, these YS cells and PS-Sp cells acquired the reconstituting potential of adult irradiated mice. Here we intended to make HSCs using this stromal cells. We differentiated ES cells labeled with GFP on OP9 stromal cell, which is supportive for Hematopoietic differentiation. After 4 days, we sorted Flk1+ cells, which is considered as a marker of hemangilblasts, and transferred them onto A-9, subline of AGM-S3, or OP9 stromal cell layer with cytokines. After several days incubation, we examined the emergence of CD34+ c-kit+ cells and colony forming ability of CD34+ or CD34− cells. CD34+ cells contained more CFU-Mix than CD34− cells. When compared on A-9 or OP9, cultured cells on OP9 contained more CFU activity than on A-9. We sorted and cultured CD34+ c-kit+ cells on OP9 for 7–10 days, and confirmed Ter119+, Gr-1+, or Mac-1+ cells differentiated from CD34+ c-kit+ cells by FACS analysis. Next, we cultured Flk1+ cells on A-9 or OP9 for 7–15 days and transplanted all the collected cells into 2.4Gy irradiated NOD-SCID mice. After 3 months after transplantation, FACS analysis showed no GFP+ cells in the recipient BM. However, PCR analysis detected donor derived DNAs in BM when Flk1+ cells were cocultured on A-9. We next transplanted 1×104 of CD34+ CD45+ or CD34+ CD45− cells from Flk1+ cells cocultured on A-9 or OP9 into 2.4 Gy irradiated NOD-SCID mice. PCR analysis revealed donor derived DNAs in mice transplanted with CD34+ CD45+ cells on A-9 and with CD34+ CD45− cell on OP9. These data suggested that CD34+ cells differentiated from Flk1+ cells have powerful hematipoietic activity and showed different potential cultured between on A-9 and on OP9.

Overexpression of HOXB4 enhances the hematopoietic potential of embryonic stem cells differentiated in vitro

Blood ◽  
1996 ◽  
Vol 87 (7) ◽  
pp. 2740-2749 ◽  
Author(s):  
CD Helgason ◽  
G Sauvageau ◽  
HJ Lawrence ◽  
C Largman ◽  
RK Humphries
Keyword(s):  
Stem Cells ◽  
Es Cells ◽  
Hematopoietic Cells ◽  
Embryonic Stem ◽  
Homeobox Genes ◽  
Embryoid Bodies ◽  
Proliferative Potential ◽  
Hematopoietic Stem ◽  
Differentiation And Proliferation

Little is known about the molecular mechanisms controlling primitive hematopoietic stem cells, especially during embryogenesis. Homeobox genes encode a family of transcription factors that have gained increasing attention as master regulators of developmental processes and recently have been implicated in the differentiation and proliferation of hematopoietic cells. Several Hox homeobox genes are now known to be differentially expressed in various subpopulations of human hematopoietic cells and one such gene, HOXB4, has recently been shown to positively determine the proliferative potential of primitive murine bone marrow cells, including cells with long-term repopulating ability. To determine if this gene might influence hematopoiesis at the earliest stages of development, embryonic stem (ES) cells were genetically modified by retroviral gene transfer to overexpress HOXB4 and the effect on their in vitro differentiation was examined. HOXB4 overexpression significantly increased the number of progenitors of mixed erythroid/myeloid colonies and definitive, but not primitive, erythroid colonies derived from embryoid bodies (EBs) at various stages after induction of differentiation. There appeared to be no significant effect on the generation of granulocytic or monocytic progenitors, nor on the efficiency of EB formation or growth rate. Analysis of mRNA from EBs derived from HOXB4-transduced ES cells on different days of primary differentiation showed a significant increase in adult beta-globin expression, with no detectable effect on GATA-1 or embryonic globin (beta H-1). Thus, HOXB4 enhances the erythropoietic, and possibly more primitive, hematopoietic differentiative potential of ES cells. These results provide new evidence implicating Hox genes in the control of very early stages in the development of the hematopoietic system and highlight the utility of the ES model for gaining insights into the molecular genetic regulation of differentiation and proliferation events.

Hematopoietic Cell Differentiation from Common Marmoset (Callithrix jacchus) Embryonic Stem Cells by Their Genetic Manipulation Using the Third Generation Lentiviral Vector.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 495-495
Author(s):  
Ryo Kurita ◽  
Erika Sasaki ◽  
Takashi Hiroyama ◽  
Tomoko Yokoo ◽  
Yukoh Nakazaki ◽  
...  
Keyword(s):  
Cell Therapy ◽  
Es Cells ◽  
Hematopoietic Cells ◽  
Embryonic Stem ◽  
Culture Conditions ◽  
Preclinical Studies ◽  
Es Cell ◽  
Hematopoietic Stem

Abstract Since the successful establishment of human embryonic stem (ES) cell lines in 1998, transplantation of differentiated ES cells to specific organ has been expected to complete its defective function. For the realistic medicine, the preclinical studies using animal model systems including non-human primates are essential. We have already demonstrated that non-human primates of common marmosets (CM) are suitable for the laboratory animal models for preclinical studies of hematopoietic stem cell therapy. In this study, we investigated the in vitro and in vivo differentiation of CM ES cells to hematopoietic cells by exogenous gene transfer methods in order to study the feasibility of future gene modified ES cell therapy. First, we tried various in vitro culture conditions including systems using embryoid bodies or co-culturing with stromal cells to induce hematopoietic cells, but the frequency of inducing hematopoietic cells was very low. The expression of CD45 and gata1 could not be detected in both conditions, suggesting that our culture conditions were incomplete for induction of hematopoietic cells from CM ES cells. Next we examined gene transduction methods by using VSV-G pseudotyped human immunodeficiency virus (HIV) vectors. We constructed the HIV vectors containing hematopoietic genes such as tal1/scl, gata1, gata2, hoxB4 and Lh2 genes under the EF1a promoter and transduced them into CM ES cells. Only in the case of tal1/scl overexpression, not other genes, hematopoietic induction from CM ES cells was dramatically increased and multi-lineage blood cells consisting of erythroid cells, granulocytes, macrophages and megakaryocytes, were confirmed by immunochemical and morphological analyses. Furthermore, RT-PCR results showed that several hematopoietic marker genes including CD34 were expressed higher in the tal1/scl overexpressed ES-derived cells. After the xenotransplantation of ES-derived cells into the immunodeficient mice, CM CD45+ cells and immature erythroids and megakaryocytic cells were observed only in the ES-tal1-injected mice, indicating that enforced expression of tal1/scl into ES cells led to highly efficient hematopoietic cell differentiation in vivo. Taken together, it was suggested that the transduction of exogenous tal1/scl cDNA into ES cells by HIV vector was the promising method for the efficient differentiation from CM ES cells to hematopoietic stem cells. Further examinations are required to determine the long-term hematopoietic reconstitute capacity and the safety of the tal1/scl transduced ES cells in marmoset for the purpose of developing new hematopoietic stem cell therapy.

Human embryonic stem cell–derived CD34+ cells: efficient production in the coculture with OP9 stromal cells and analysis of lymphohematopoietic potential

Blood ◽  
2005 ◽  
Vol 105 (2) ◽  
pp. 617-626 ◽  
Author(s):  
Maxim A. Vodyanik ◽  
Jack A. Bork ◽  
James A. Thomson ◽  
Igor I. Slukvin
Keyword(s):  
Stem Cell ◽  
Stromal Cells ◽  
Es Cells ◽  
Embryonic Stem ◽  
Efficient Production ◽  
Alternative Source ◽  
Hematopoietic Stem ◽  
Cd34 Cells ◽  
Hes Cells

AbstractEmbryonic stem (ES) cells have the potential to serve as an alternative source of hematopoietic precursors for transplantation and for the study of hematopoietic cell development. Using coculture of human ES (hES) cells with OP9 bone marrow stromal cells, we were able to obtain up to 20% of CD34+ cells and isolate up to 107 CD34+ cells with more than 95% purity from a similar number of initially plated hES cells after 8 to 9 days of culture. The hES cell–derived CD34+ cells were highly enriched in colony-forming cells, cells expressing hematopoiesis-associated genes GATA-1, GATA-2, SCL/TAL1, and Flk-1, and retained clonogenic potential after in vitro expansion. CD34+ cells displayed the phenotype of primitive hematopoietic progenitors as defined by co-expression of CD90, CD117, and CD164, along with a lack of CD38 expression and contained aldehyde dehydrogenase–positive cells as well as cells with verapamil-sensitive ability to efflux rhodamine 123. When cultured on MS-5 stromal cells in the presence of stem cell factor, Flt3-L, interleukin 7 (IL-7), and IL-3, isolated CD34+ cells differentiated into lymphoid (B and natural killer cells) as well as myeloid (macrophages and granulocytes) lineages. These data indicate that CD34+ cells generated through hES/OP9 coculture display several features of definitive hematopoietic stem cells.

Production of functional platelets by differentiated embryonic stem (ES) cells in vitro

Blood ◽  
2003 ◽  
Vol 102 (12) ◽  
pp. 4044-4051 ◽  
Author(s):  
Tetsuro-Takahiro Fujimoto ◽  
Satoshi Kohata ◽  
Hidenori Suzuki ◽  
Hiroshi Miyazaki ◽  
Kingo Fujimura
Keyword(s):  
Stromal Cells ◽  
Culture Medium ◽  
Es Cells ◽  
Blood Platelets ◽  
Embryonic Stem ◽  
Clinical Applications ◽  
Platelet Production ◽  
Transmission Electron ◽  
Second Wave

Abstract Megakaryocytes and functional platelets were generated in vitro from murine embryonic stem (ES) cells with the use of a coculture system with stromal cells. Two morphologically distinctive megakaryocytes were observed sequentially. Small megakaryocytes rapidly produced proplatelets on day 8 of the differentiation, and large hyperploid megakaryocytes developed after day 12, suggesting primitive and definitive megakaryopoiesis. Two waves of platelet production were consistently observed in the culture medium. A larger number of platelets was produced in the second wave; 104 ES cells produced up to 108 platelets. By transmission electron microscopy, platelets from the first wave were relatively rounder with a limited number of granules, but platelets from the second wave were discoid shaped with well-developed granules that were indistinguishable from peripheral blood platelets. ES-derived platelets were functional since they bound fibrinogen, formed aggregates, expressed P-selectin upon stimulation, and fully spread on immobilized fibrinogen. These results show the potential utility of ES-derived platelets for clinical applications. Furthermore, production of gene-transferred platelets was achieved by differentiating ES cells that were transfected with genes of interest. Overexpression of the cytoplasmic domain of integrin β3 in the ES-derived platelets prevented the activation of αIIbβ3, demonstrating that this system will facilitate functional platelet studies. (Blood. 2003;102:4044-4051)

scholarly journals Transcriptome Analysis of Dnmt3l Knock-Out Mice Derived Multipotent Mesenchymal Stem/Stromal Cells During Osteogenic Differentiation

2021 ◽  
Vol 9 ◽  
Author(s):  
Chih-Yi Yang ◽  
Rita Jui-Hsien Lu ◽  
Ming-Kang Lee ◽  
Felix Shih-Hsian Hsiao ◽  
Ya-Ping Yen ◽  
...  
Keyword(s):  
Stromal Cells ◽  
Dna Methyltransferase ◽  
Bone Development ◽  
Es Cells ◽  
Embryonic Stem ◽  
Differentiation Potential ◽  
Knock Out ◽  
Cell Based Therapy

Multipotent mesenchymal stem/stromal cells (MSCs) exhibit great potential for cell-based therapy. Proper epigenomic signatures in MSCs are important for the maintenance and the subsequent differentiation potential. The DNA methyltransferase 3-like (DNMT3L) that was mainly expressed in the embryonic stem (ES) cells and the developing germ cells plays an important role in shaping the epigenetic landscape. Here, we report the reduced colony forming ability and impaired in vitro osteogenesis in Dnmt3l-knockout-mice-derived MSCs (Dnmt3l KO MSCs). By comparing the transcriptome between undifferentiated Dnmt3l KO MSCs and the MSCs from the wild-type littermates, some of the differentially regulated genes (DEGs) were found to be associated with bone-morphology-related phenotypes. On the third day of osteogenic induction, differentiating Dnmt3l KO MSCs were enriched for genes associated with nucleosome structure, peptide binding and extracellular matrix modulation. Differentially expressed transposable elements in many subfamilies reflected the change of corresponding regional epigenomic signatures. Interestingly, DNMT3L protein is not expressed in cultured MSCs. Therefore, the observed defects in Dnmt3l KO MSCs are unlikely a direct effect from missing DNMT3L in this cell type; instead, we hypothesized them as an outcome of the pre-deposited epigenetic signatures from the DNMT3L-expressing progenitors. We observed that 24 out of the 107 upregulated DEGs in Dnmt3l KO MSCs were hypermethylated in their gene bodies of DNMT3L knock-down ES cells. Among these 24 genes, some were associated with skeletal development or homeostasis. However, we did not observe reduced bone development, or reduced bone density through aging in vivo. The stronger phenotype in vitro suggested the involvement of potential spreading and amplification of the pre-deposited epigenetic defects over passages, and the contribution of oxidative stress during in vitro culture. We demonstrated that transient deficiency of epigenetic co-factor in ES cells or progenitor cells caused compromised property in differentiating cells much later. In order to facilitate safer practice in cell-based therapy, we suggest more in-depth examination shall be implemented for cells before transplantation, even on the epigenetic level, to avoid long-term risk afterward.

Transcriptional heterogeneity in mouse embryonic stem cells

2009 ◽  
Vol 21 (1) ◽  
pp. 67 ◽  
Author(s):  
Tetsuya S. Tanaka
Keyword(s):  
Cell Fate ◽  
Es Cells ◽  
Embryonic Stem ◽  
Cell Types ◽  
The Body ◽  
Cell Subpopulation ◽  
Es Cell ◽  
Differentiation Potential ◽  
Mouse Es Cells

The embryonic stem (ES) cell is a stem cell derived from early embryos that can indefinitely repeat self-renewing cell division cycles as an undifferentiated cell in vitro and give rise to all specialised cell types in the body. However, manipulating ES cell differentiation in vitro is a challenge due to, at least in part, heterogeneous gene induction. Recent experimental evidence has demonstrated that undifferentiated mouse ES cells maintained in culture exhibit heterogeneous expression of Dppa3, Nanog, Rex1, Pecam1 and Zscan4 as well as genes (Brachyury/T, Rhox6/9 and Twist2) normally expressed in specialised cell types. The Nanog-negative, Rex1-negative or T-positive ES cell subpopulation has a unique differentiation potential. Thus, studying the mechanism that generates ES cell subpopulations will improve manipulation of ES cell fate and help our understanding of the nature of embryonic development.

CD41+ and Vascular Endothelial (VE)-Cadherin+ Cells: Two Developmental Origins of Hematopoietic Cell Lineages That Show Different Hematogenic Potentials.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 3612-3612
Author(s):  
Kazuaki Hashimoto ◽  
Xin Huang ◽  
Yuri Shimoda ◽  
Guoyou Dai ◽  
Tetsuhiro Fujimoto ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Cell Population ◽  
Stromal Cells ◽  
Es Cells ◽  
Hematopoietic Cells ◽  
Yolk Sac ◽  
Mouse Embryos ◽  
Developmental Origins ◽  
Cell Lineages

Abstract It has been proposed that the definitive hematopoietic cell lineages are derived from hemogenic endothelial cells. Recently, CD41 was identified as an earliest cell surface marker of hematopoietic progenitor cells during mouse embryogenesis. We examined relationship between VE-cadherin+ hemogenic endothelial cells and CD41+ progenitors as developmental origins of hematopoietic cells by using in vitro differentiation system of ES cells as well as mouse embryos. FACS analyses on ES cells differentiating on OP9 stromal cells identified two cell populations, CD41+CD45− and CD41lowVE-cadherin+CD45−. The CD41+ cell population was derived from Flk1+ cells that represent lateral plate mesoderm but not from PDGFRa+ cells that represent paraxial mesoderm. CD41 expression on CD41+CD45− cells was weak at Day4 of ES cell culture. CD41+CD45− cells rapidly increased in number and CD41 expression became higher after Day5. CD45+ cells became detectable as a subpopulation of CD41+ cells two days after the appearance of the CD41+CD45− cell population. A significant proportion of the purified CD41lowVE-cadherin+CD45− cells differentiated to cells with CD41+CD45− phenotype in short-term culture, while CD41+CD45− cells did not differentiate into VE-cadherin+ cells. Unsurprisingly only CD41lowVE-cadherin+CD45− population had potential to produce endothelial cell colonies on OP9 cell layer. Liquid cultures and methylcellulose colony assay with a proper combination of cytokines showed that primitive erythroid colony forming cells were highly enriched in the CD41+CD45− cell population. CD41+CD45− cells also differentiated to Ter119+ definitive erythrocytes and Gr-1+ and Mac-1+ myeloid cells. In contrast, CD41lowVE-cadherin+CD45− cells produced only few hematopoietic cells in the same condition. However, CD41lowVE-cadherin+CD45− cells were capable of differentiating into multi-lineage hematopoietic cells including B lymphocytes when cultured with OP9 stromal cells. CD41+CD45− cells did not show any B lymphogenic potentials even when cultured with OP9 cells. We examined hemogenic potentials of phenotypically equivalent cells purified from mouse embryos. FACS analyses on cells dissociated from yolk sac and lower trunk of embryos proper revealed two distinct populations, CD41+CD45− cells and CD41−/lowVE-cadherin+CD45− cells. Both populations were already detectable in 8.5 dpc embryos. CD41−/lowVE-cadherin+CD45− cells but not CD41+CD45− cells produced endothelial cell colonies in vitro. The CD41−/lowVE-cadherin+CD45− cell population isolated from yolk sac was able to differentiate into multi-lineage hematopoietic cells when cultured with OP9 cells. However, the same population that was isolated from embryos proper had very poor potential to generate erythroid and myeloid cells although it still initiated robust production of B lymphocytes. Nevertheless, hemogenic activities of this population declined to undetectable level on 11.5 dpc. In contrast, CD41+CD45− cells isolated from yolk sac and embryos proper gave rise to multilineage hematopoietic cells and those potentials were stronger than that of yolk sac-derived CD41−/lowVE-cadherin+CD45− cells. Our results suggest that two distinct precursors, hemogenic endothelial cells and CD41+ progenitor cells, may contribute to the initiation of definitive hematopoiesis in mouse ontogeny, although activity of hemogenic endothelial cells in embryo proper might be unexpectedly limited.

Osteoclasts From Human Embryonic Stem Cell-Derived Hematopoietic Progenitors Support Development of An in Vitro Niche Microenvironment.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 2517-2517
Author(s):  
Mohammad Saiful Islam ◽  
Jeremy R Allred ◽  
Katherine L Hill ◽  
Melinda K Hexum ◽  
Dan S. Kaufman
Keyword(s):  
Bone Marrow ◽  
Stromal Cells ◽  
Peripheral Blood ◽  
Conflicts Of Interest ◽  
Osteoclast Differentiation ◽  
Hematopoietic Cells ◽  
Embryonic Stem ◽  
Pit Formation ◽  
Hematopoietic Niche

Abstract Abstract 2517 Poster Board II-494 Osteoclasts are bone resorbing cells located in the bone marrow that play a key role in hematopoiesis and formation of the hematopoietic niche. Previous studies demonstrate osteoclasts arise from the monocyte-macrophage lineage of cells within the bone marrow microenvironment. Osteoclast progenitor cells typically express the monocyte marker CD14, though relatively little is known about the developmental history of these osteoclastogeneic cells in humans. Osteoclast progenitors have been previously isolated from peripheral blood and bone marrow. Previous studies by our group and others demonstrate human embryonic stem cells (hESCs) can differentiate into CD34+CD45+ cells that can be supported to differentiate into many types of hematopoietic cells, though development of osteoclasts have not been previously demonstrated. To better evaluate osteoclastogenesis, hESCs were allowed to differentiate on M210 stromal cells for 19–21 days then sorted for CD34+CD45+ cells. These cells were placed into a secondary co-culture with M210 stromal cells using osteoclast differentiation factors macrophage colony-stimulating factor (hM-CSF) and receptor activator of nuclear factor–kB ligand (hRANKL) for 14–21 days. During this time, mononuclear hematopoietic cells expanded on top of the stromal cells, followed by appearance of multinucleated cells that became adherent and embedded within the stromal cell layer. These adherent multi-nucleated cells were TRAP-positive, consistent with osteoclasts. Q-RT-PCR analysis demonstrated expression of osteoclast genes NFATC1, TRAP, CATHEPSIN K AND MMP-9. Culturing these putative osteoclasts on dentin discs demonstrated dentin resorption and pit formation, consistent with osteoclasts cultured from peripheral blood. No pit formation observed when the same experiments were done without hRANKL and hMCSF. Most remarkable was the extensive proliferation of CD45+CD33+ myeloid cells around the periphery of the adherent, multinucleated osteoclasts in culture, resembling a multi-cellular hematopoietic niche environment. Further studies are underway to better evaluate the interaction of these osteoclast cells with other hESC-derived hematopoietic cells. Together, these studies demonstrate development of functional osteoclasts directly from hESC-derived CD34+CD45+ hematopoietic progenitor population. We also show development of a novel in vitro HSC niche microenvironment utilizing hESC-derived osteoclasts. This system has the potential to now incorporate other hESC-derived cell populations as a model to better define cellular and extracellular mechanisms that mediate human hematopoietic development. Disclosures: No relevant conflicts of interest to declare.

scholarly journals The dyskerin ribonucleoprotein complex as an OCT4/SOX2 coactivator in embryonic stem cells

eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Yick W Fong ◽  
Jaclyn J Ho ◽  
Carla Inouye ◽  
Robert Tjian
Keyword(s):  
Stem Cell ◽  
Es Cells ◽  
Embryonic Stem ◽  
In Vitro Transcription ◽  
Specific Gene ◽  
Transcriptional Level ◽  
Ips Cell ◽  
Ribonucleoprotein Complex ◽  
Transcription System

Acquisition of pluripotency is driven largely at the transcriptional level by activators OCT4, SOX2, and NANOG that must in turn cooperate with diverse coactivators to execute stem cell-specific gene expression programs. Using a biochemically defined in vitro transcription system that mediates OCT4/SOX2 and coactivator-dependent transcription of the Nanog gene, we report the purification and identification of the dyskerin (DKC1) ribonucleoprotein complex as an OCT4/SOX2 coactivator whose activity appears to be modulated by a subset of associated small nucleolar RNAs (snoRNAs). The DKC1 complex occupies enhancers and regulates the expression of key pluripotency genes critical for self-renewal in embryonic stem (ES) cells. Depletion of DKC1 in fibroblasts significantly decreased the efficiency of induced pluripotent stem (iPS) cell generation. This study thus reveals an unanticipated transcriptional role of the DKC1 complex in stem cell maintenance and somatic cell reprogramming.

Sign in / Sign up

Export Citation Format

Share Document