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Kovuru N, Mochizuki-Kashio M, Menna T, Jeffrey G, Hong Y, Me Yoon Y, Zhang Z, Kurre P. Deregulated protein homeostasis constrains fetal hematopoietic stem cell pool expansion in Fanconi anemia. Nat Commun 2024; 15:1852. [PMID: 38424108 PMCID: PMC10904799 DOI: 10.1038/s41467-024-46159-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 02/15/2024] [Indexed: 03/02/2024] Open
Abstract
Demand-adjusted and cell type specific rates of protein synthesis represent an important safeguard for fate and function of long-term hematopoietic stem cells. Here, we identify increased protein synthesis rates in the fetal hematopoietic stem cell pool at the onset of hematopoietic failure in Fanconi Anemia, a prototypical DNA repair disorder that manifests with bone marrow failure. Mechanistically, the accumulation of misfolded proteins in Fancd2-/- fetal liver hematopoietic stem cells converges on endoplasmic reticulum stress, which in turn constrains midgestational expansion. Restoration of protein folding by the chemical chaperone tauroursodeoxycholic acid, a hydrophilic bile salt, prevents accumulation of unfolded proteins and rescues Fancd2-/- fetal liver long-term hematopoietic stem cell numbers. We find that proteostasis deregulation itself is driven by excess sterile inflammatory activity in hematopoietic and stromal cells within the fetal liver, and dampened Type I interferon signaling similarly restores fetal Fancd2-/- long-term hematopoietic stem cells to wild type-equivalent numbers. Our study reveals the origin and pathophysiological trigger that gives rise to Fanconi anemia hematopoietic stem cell pool deficits. More broadly, we show that fetal protein homeostasis serves as a physiological rheostat for hematopoietic stem cell fate and function.
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Affiliation(s)
- Narasaiah Kovuru
- Comprehensive Bone Marrow Failure Center, Children's Hospital of Philadelphia; Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Makiko Mochizuki-Kashio
- Department of Microscopic and Developmental Anatomy, Tokyo Women's Medical University, Tokyo, Japan
| | - Theresa Menna
- Comprehensive Bone Marrow Failure Center, Children's Hospital of Philadelphia; Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Greer Jeffrey
- Comprehensive Bone Marrow Failure Center, Children's Hospital of Philadelphia; Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yuning Hong
- La Trobe University, Department of Biochemistry and Chemistry, Melbourne, Australia
| | - Young Me Yoon
- Committee on Immunology, Graduate Program in Biosciences, University of Chicago, Chicago, IL, USA
| | - Zhe Zhang
- Department of Biomedical and Health Informatics, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Peter Kurre
- Comprehensive Bone Marrow Failure Center, Children's Hospital of Philadelphia; Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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2
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Marion W, Koppe T, Chen CC, Wang D, Frenis K, Fierstein S, Sensharma P, Aumais O, Peters M, Ruiz-Torres S, Chihanga T, Boettcher S, Shimamura A, Bauer DE, Schlaeger T, Wells SI, Ebert BL, Starczynowski D, da Rocha EL, Rowe RG. RUNX1 mutations mitigate quiescence to promote transformation of hematopoietic progenitors in Fanconi anemia. Leukemia 2023; 37:1698-1708. [PMID: 37391485 PMCID: PMC11009868 DOI: 10.1038/s41375-023-01945-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 05/25/2023] [Accepted: 06/13/2023] [Indexed: 07/02/2023]
Abstract
Many inherited bone marrow failure syndromes (IBMFSs) present a high risk of transformation to myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). During transformation of IBMFSs, hematopoietic stem and progenitor cells (HSPCs) with poor fitness gain ectopic, dysregulated self-renewal secondary to somatic mutations via undefined mechanisms. Here, in the context of the prototypical IBMFS Fanconi anemia (FA), we performed multiplexed gene editing of mutational hotspots in MDS-associated genes in human induced pluripotent stem cells (iPSCs) followed by hematopoietic differentiation. We observed aberrant self-renewal and impaired differentiation of HSPCs with enrichment of RUNX1 insertions and deletions (indels), generating a model of IBMFS-associated MDS. We observed that compared to the failure state, FA MDS cells show mutant RUNX1-mediated blunting of the G1/S cell cycle checkpoint that is normally activated in FA in response to DNA damage. RUNX1 indels also lead to activation of innate immune signaling, which stabilizes the homologous recombination (HR) effector BRCA1, and this pathway can be targeted to abrogate viability and restore sensitivity to genotoxins in FA MDS. Together, these studies develop a paradigm for modeling clonal evolution in IBMFSs, provide basic understanding of the pathogenesis of MDS, and uncover a therapeutic target in FA-associated MDS.
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Affiliation(s)
- William Marion
- Department of Hematology-Oncology, Boston Children's Hospital, Boston, MA, USA
- Stem Cell Program, Boston Children's Hospital, Boston, MA, USA
| | - Tiago Koppe
- Department of Hematology-Oncology, Boston Children's Hospital, Boston, MA, USA
- Stem Cell Program, Boston Children's Hospital, Boston, MA, USA
| | - Chun-Chin Chen
- Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Dahai Wang
- Department of Hematology-Oncology, Boston Children's Hospital, Boston, MA, USA
- Stem Cell Program, Boston Children's Hospital, Boston, MA, USA
| | - Katie Frenis
- Department of Hematology-Oncology, Boston Children's Hospital, Boston, MA, USA
- Stem Cell Program, Boston Children's Hospital, Boston, MA, USA
| | - Sara Fierstein
- Department of Hematology-Oncology, Boston Children's Hospital, Boston, MA, USA
- Stem Cell Program, Boston Children's Hospital, Boston, MA, USA
| | - Prerana Sensharma
- Department of Hematology-Oncology, Boston Children's Hospital, Boston, MA, USA
- Stem Cell Program, Boston Children's Hospital, Boston, MA, USA
| | - Olivia Aumais
- Department of Hematology-Oncology, Boston Children's Hospital, Boston, MA, USA
| | - Michael Peters
- Department of Hematology-Oncology, Boston Children's Hospital, Boston, MA, USA
| | | | | | - Steffen Boettcher
- Dana-Farber Cancer Institute, Boston, MA, USA
- Department of Medical Oncology and Hematology, University of Zurich and University Hospital of Zurich, Zurich, Switzerland
| | - Akiko Shimamura
- Department of Hematology-Oncology, Boston Children's Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Daniel E Bauer
- Department of Hematology-Oncology, Boston Children's Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | | | - Susanne I Wells
- Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Benjamin L Ebert
- Dana-Farber Cancer Institute, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
- Howard Hughes Medical Institute, Boston, MA, USA
| | - Daniel Starczynowski
- Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- University of Cincinnati Cancer Center, Cincinnati, OH, USA
| | | | - R Grant Rowe
- Department of Hematology-Oncology, Boston Children's Hospital, Boston, MA, USA.
- Stem Cell Program, Boston Children's Hospital, Boston, MA, USA.
- Harvard Medical School, Boston, MA, USA.
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3
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Mochizuki-Kashio M, Otsuki N, Fujiki K, Abdelhamd S, Kurre P, Grompe M, Iwama A, Saito K, Nakamura-Ishizu A. Replication stress increases mitochondrial metabolism and mitophagy in FANCD2 deficient fetal liver hematopoietic stem cells. Front Oncol 2023; 13:1108430. [PMID: 37007148 PMCID: PMC10061350 DOI: 10.3389/fonc.2023.1108430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Accepted: 01/30/2023] [Indexed: 03/09/2023] Open
Abstract
Fanconi Anemia (FA) is an inherited bone marrow (BM) failure disorder commonly diagnosed during school age. However, in murine models, disrupted function of FA genes leads to a much earlier decline in fetal liver hematopoietic stem cell (FL HSC) number that is associated with increased replication stress (RS). Recent reports have shown mitochondrial metabolism and clearance are essential for long-term BM HSC function. Intriguingly, impaired mitophagy has been reported in FA cells. We hypothesized that RS in FL HSC impacts mitochondrial metabolism to investigate fetal FA pathophysiology. Results show that experimentally induced RS in adult murine BM HSCs evoked a significant increase in mitochondrial metabolism and mitophagy. Reflecting the physiological RS during development in FA, increase mitochondria metabolism and mitophagy were observed in FANCD2-deficient FL HSCs, whereas BM HSCs from adult FANCD2-deficient mice exhibited a significant decrease in mitophagy. These data suggest that RS activates mitochondrial metabolism and mitophagy in HSC.
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Affiliation(s)
- Makiko Mochizuki-Kashio
- Department of Mieroscopic and Developmental Anatomy, Tokyo Women's Medical University, Tokyo, Japan
| | - Noriko Otsuki
- Institute of Medical Genetics, Tokyo Women's Medical University, Tokyo, Japan
| | - Kota Fujiki
- Department of Hygiene and Fublic Health, Tokyo Women's Medical University, Tokyo, Japan
| | - Sherif Abdelhamd
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, TN, United States
| | - Peter Kurre
- Children's Hospital of Philadelphia, Comprehensive Bone Marrow Failure Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Markus Grompe
- Papé Family Pediatric Research Institute, Oregon Stem Cell Center, Oregon Health & Science University, Portland, OR, United States
| | - Atsushi Iwama
- Division of Stem Cell and Molecular Medicine, Center for Stem Cell Biology and Regenerative Medicine, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Kayoko Saito
- Institute of Medical Genetics, Tokyo Women's Medical University, Tokyo, Japan
| | - Ayako Nakamura-Ishizu
- Department of Mieroscopic and Developmental Anatomy, Tokyo Women's Medical University, Tokyo, Japan
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4
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Jarysta A, Riou L, Firlej V, Lapoujade C, Kortulewski T, Barroca V, Gille AS, Dumont F, Jacques S, Letourneur F, Rosselli F, Allemand I, Fouchet P. Abnormal migration behavior linked to Rac1 signaling contributes to primordial germ cell exhaustion in Fanconi anemia pathway-deficient Fancg-/- embryos. Hum Mol Genet 2021; 31:97-110. [PMID: 34368842 PMCID: PMC8682768 DOI: 10.1093/hmg/ddab222] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 06/04/2021] [Accepted: 07/05/2021] [Indexed: 11/16/2022] Open
Abstract
Fanconi anemia (FA) is a rare human genetic disorder characterized by bone marrow failure, predisposition to cancer and developmental defects including hypogonadism. Reproductive defects leading to germ cell aplasia are the most consistent phenotypes seen in FA mouse models. We examined the role of the nuclear FA core complex gene Fancg in the development of primordial germ cells (PGCs), the embryonic precursors of adult gametes, during fetal development. PGC maintenance was severely impaired in Fancg−/− embryos. We observed a defect in the number of PGCs starting at E9.5 and a strong attrition at E11.5 and E13.5. Remarkably, we observed a mosaic pattern reflecting a portion of testicular cords devoid of PGCs in E13.5 fetal gonads. Our in vitro and in vivo data highlight a potential role of Fancg in the proliferation and in the intrinsic cell motility abilities of PGCs. The random migratory process is abnormally activated in Fancg−/− PGCs, altering the migration of cells. Increased cell death and PGC attrition observed in E11.5 Fancg−/− embryos are features consistent with delayed migration of PGCs along the migratory pathway to the genital ridges. Moreover, we show that an inhibitor of RAC1 mitigates the abnormal migratory pattern observed in Fancg−/− PGCs.
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Affiliation(s)
- Amandine Jarysta
- Université de Paris and Université Paris-Saclay, iRCM/IBFJ CEA, UMR Stabilité Génétique Cellules Souches et Radiations, Laboratoire des Cellules Souches Germinales, F-92265, Fontenay-aux-Roses, France
| | - Lydia Riou
- Université de Paris and Université Paris-Saclay, iRCM/IBFJ CEA, UMR Stabilité Génétique Cellules Souches et Radiations, Laboratoire des Cellules Souches Germinales, F-92265, Fontenay-aux-Roses, France
| | - Virginie Firlej
- Université de Paris and Université Paris-Saclay, iRCM/IBFJ CEA, UMR Stabilité Génétique Cellules Souches et Radiations, Laboratoire des Cellules Souches Germinales, F-92265, Fontenay-aux-Roses, France
| | - Clémentine Lapoujade
- Université de Paris and Université Paris-Saclay, iRCM/IBFJ CEA, UMR Stabilité Génétique Cellules Souches et Radiations, Laboratoire des Cellules Souches Germinales, F-92265, Fontenay-aux-Roses, France
| | - Thierry Kortulewski
- Université de Paris and Université Paris-Saclay, Inserm, iRCM/IBFJ CEA, UMR Stabilité Génétique Cellules Souches et Radiations, Laboratoire de RadioPathologie, F-92265, Fontenay-aux-Roses, France
| | - Vilma Barroca
- Université de Paris and Université Paris-Saclay, Inserm, iRCM/IBFJ CEA, UMR Stabilité Génétique Cellules Souches et Radiations, F-92265, Fontenay-aux-Roses, France
| | - Anne-Sophie Gille
- Université de Paris and Université Paris-Saclay, iRCM/IBFJ CEA, UMR Stabilité Génétique Cellules Souches et Radiations, Laboratoire des Cellules Souches Germinales, F-92265, Fontenay-aux-Roses, France.,Département de Génétique, Développement et Cancer. Team From Gametes to Birth, Institut Cochin, INSERM U1016, Paris, France
| | - Florent Dumont
- Université Paris Saclay, UMS IPSIT, F-92296, Châtenay-Malabry, France
| | - Sébastien Jacques
- Plate-Forme Séquençage et Génomique, Institut Cochin, Inserm U1016, Université de Paris, 22 rue Méchain, 75014 Paris, France
| | - Franck Letourneur
- Plate-Forme Séquençage et Génomique, Institut Cochin, Inserm U1016, Université de Paris, 22 rue Méchain, 75014 Paris, France
| | - Filippo Rosselli
- CNRS-UMR9019, Intégrité du Génome et Cancers, Equipe Labellisée « La Ligue Contre Le cancer », Gustave Roussy Cancer Center, Université Paris-Saclay, 94805 Villejuif, France
| | - Isabelle Allemand
- Université de Paris and Université Paris-Saclay, iRCM/IBFJ CEA, UMR Stabilité Génétique Cellules Souches et Radiations, Laboratoire des Cellules Souches Germinales, F-92265, Fontenay-aux-Roses, France
| | - Pierre Fouchet
- Université de Paris and Université Paris-Saclay, iRCM/IBFJ CEA, UMR Stabilité Génétique Cellules Souches et Radiations, Laboratoire des Cellules Souches Germinales, F-92265, Fontenay-aux-Roses, France
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5
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An induced pluripotent stem cell model of Fanconi anemia reveals mechanisms of p53-driven progenitor cell differentiation. Blood Adv 2020; 4:4679-4692. [PMID: 33002135 DOI: 10.1182/bloodadvances.2020001593] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 08/26/2020] [Indexed: 12/17/2022] Open
Abstract
Fanconi anemia (FA) is a disorder of DNA repair that manifests as bone marrow (BM) failure. The lack of accurate murine models of FA has refocused efforts toward differentiation of patient-derived induced pluripotent stem cells (IPSCs) to hematopoietic progenitor cells (HPCs). However, an intact FA DNA repair pathway is required for efficient IPSC derivation, hindering these efforts. To overcome this barrier, we used inducible complementation of FANCA-deficient IPSCs, which permitted robust maintenance of IPSCs. Modulation of FANCA during directed differentiation to HPCs enabled the production of FANCA-deficient human HPCs that recapitulated FA genotoxicity and hematopoietic phenotypes relative to isogenic FANCA-expressing HPCs. FANCA-deficient human HPCs underwent accelerated terminal differentiation driven by activation of p53/p21. We identified growth arrest specific 6 (GAS6) as a novel target of activated p53 in FANCA-deficient HPCs and modulate GAS6 signaling to rescue hematopoiesis in FANCA-deficient cells. This study validates our strategy to derive a sustainable, highly faithful human model of FA, uncovers a mechanism of HPC exhaustion in FA, and advances toward future cell therapy in FA.
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6
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Domenech C, Maillard L, Rousseau A, Guidez F, Petit L, Pla M, Clay D, Guimiot F, Sanfilippo S, Jacques S, de la Grange P, Robil N, Soulier J, Souyri M. Studies in an Early Development Window Unveils a Severe HSC Defect in both Murine and Human Fanconi Anemia. Stem Cell Reports 2018; 11:1075-1091. [PMID: 30449320 PMCID: PMC6234961 DOI: 10.1016/j.stemcr.2018.10.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 09/27/2018] [Accepted: 10/01/2018] [Indexed: 01/05/2023] Open
Abstract
Fanconi anemia (FA) causes bone marrow failure early during childhood, and recent studies indicate that a hematopoietic defect could begin in utero. We performed a unique kinetics study of hematopoiesis in Fancg-/- mouse embryos, between the early embryonic day 11.5 (E11.5) to E12.5 developmental window (when the highest level of hematopoietic stem cells [HSC] amplification takes place) and E14.5. This study reveals a deep HSC defect with exhaustion of proliferative and self-renewal capacities very early during development, together with severe FA clinical and biological manifestations, which are mitigated at E14.5 due to compensatory mechanisms that help to ensure survival of Fancg-/- embryos. It also reports that a deep HSC defect is also observed during human FA development, and that human FA fetal liver (FL) HSCs present a transcriptome profile similar to that of mouse E12.5 Fancg-/- FL HSCs. Altogether, our results highlight that early mouse FL could represent a good alternative model for studying Fanconi pathology.
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Affiliation(s)
- Carine Domenech
- CNRS UMR7622/IBPS, Paris, France; Université Pierre et Marie Curie, Sorbonne Universités, Paris, France; INSERM UMR_S1131, Hôpital Saint Louis, Paris, France; IUH, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Loïc Maillard
- CNRS UMR7622/IBPS, Paris, France; Université Pierre et Marie Curie, Sorbonne Universités, Paris, France; INSERM UMR_S1131, Hôpital Saint Louis, Paris, France; IUH, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Alix Rousseau
- IUH, Université Paris Diderot, Sorbonne Paris Cité, Paris, France; INSERM U944/CNRS UMR7212, Hôpital Saint Louis, Paris, France
| | - Fabien Guidez
- INSERM UMR_S1131, Hôpital Saint Louis, Paris, France; IUH, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Laurence Petit
- CNRS UMR7622/IBPS, Paris, France; Université Pierre et Marie Curie, Sorbonne Universités, Paris, France
| | - Marika Pla
- INSERM UMR_S1131, Hôpital Saint Louis, Paris, France; IUH, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Denis Clay
- INSERM U972, Hôpital Paul Brousse, Villejuif, France; Plateforme de cytométrie, UMS33, Université Paris Sud, Villejuif, France
| | - Fabien Guimiot
- Service de Foetopathologie, Hôpital Robert Debré, Paris, France
| | - Sandra Sanfilippo
- CNRS UMR7622/IBPS, Paris, France; Université Pierre et Marie Curie, Sorbonne Universités, Paris, France
| | | | | | | | - Jean Soulier
- IUH, Université Paris Diderot, Sorbonne Paris Cité, Paris, France; INSERM U944/CNRS UMR7212, Hôpital Saint Louis, Paris, France
| | - Michèle Souyri
- CNRS UMR7622/IBPS, Paris, France; Université Pierre et Marie Curie, Sorbonne Universités, Paris, France; INSERM UMR_S1131, Hôpital Saint Louis, Paris, France; IUH, Université Paris Diderot, Sorbonne Paris Cité, Paris, France.
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7
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Kurre P. Hematopoietic development: a gap in our understanding of inherited bone marrow failure. Exp Hematol 2017; 59:1-8. [PMID: 29248612 DOI: 10.1016/j.exphem.2017.12.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 11/26/2017] [Accepted: 12/07/2017] [Indexed: 12/31/2022]
Abstract
Inherited bone marrow failure syndromes (IBMFS) represent a heterogeneous group of multisystem disorders that typically present with cytopenia in early childhood. Efforts to understand the underlying hematopoietic stem cell (HSC) losses have generally focused on postnatal hematopoiesis. However, reflecting the role of many of the involved genes in core cellular functions and the diverse nonhematologic abnormalities seen in patients at birth, studies have begun to explore IBMFS manifestations during fetal development. Here, I consider the current evidence for fetal deficits in the HSC pool and highlight emerging concepts regarding the origins and unique pathophysiology of hematopoietic failure in IBMFS.
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Affiliation(s)
- Peter Kurre
- Department of Pediatrics, Papé Family Pediatric Research Institute, Pediatric Blood & Cancer Biology Program, Oregon Health & Science University, Portland, Oregon.
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8
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Botthof JG, Bielczyk-Maczyńska E, Ferreira L, Cvejic A. Loss of the homologous recombination gene rad51 leads to Fanconi anemia-like symptoms in zebrafish. Proc Natl Acad Sci U S A 2017; 114:E4452-E4461. [PMID: 28512217 PMCID: PMC5465903 DOI: 10.1073/pnas.1620631114] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
RAD51 is an indispensable homologous recombination protein, necessary for strand invasion and crossing over. It has recently been designated as a Fanconi anemia (FA) gene, following the discovery of two patients carrying dominant-negative mutations. FA is a hereditary DNA-repair disorder characterized by various congenital abnormalities, progressive bone marrow failure, and cancer predisposition. In this report, we describe a viable vertebrate model of RAD51 loss. Zebrafish rad51 loss-of-function mutants developed key features of FA, including hypocellular kidney marrow, sensitivity to cross-linking agents, and decreased size. We show that some of these symptoms stem from both decreased proliferation and increased apoptosis of embryonic hematopoietic stem and progenitor cells. Comutation of p53 was able to rescue the hematopoietic defects seen in the single mutants, but led to tumor development. We further demonstrate that prolonged inflammatory stress can exacerbate the hematological impairment, leading to an additional decrease in kidney marrow cell numbers. These findings strengthen the assignment of RAD51 as a Fanconi gene and provide more evidence for the notion that aberrant p53 signaling during embryogenesis leads to the hematological defects seen later in life in FA. Further research on this zebrafish FA model will lead to a deeper understanding of the molecular basis of bone marrow failure in FA and the cellular role of RAD51.
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Affiliation(s)
- Jan Gregor Botthof
- Department of Haematology, University of Cambridge, Addenbrookes Hospital, Cambridge CB2 0XY, United Kingdom
- Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
- Wellcome Trust-Medical Research Council Cambridge Stem Cell Institute, Cambridge CB2 1QR, United Kingdom
| | - Ewa Bielczyk-Maczyńska
- Department of Haematology, University of Cambridge, Addenbrookes Hospital, Cambridge CB2 0XY, United Kingdom
- Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
- National Health Service Blood and Transplant, Cambridge CB2 0PT, United Kingdom
| | - Lauren Ferreira
- Department of Haematology, University of Cambridge, Addenbrookes Hospital, Cambridge CB2 0XY, United Kingdom
- Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
- Wellcome Trust-Medical Research Council Cambridge Stem Cell Institute, Cambridge CB2 1QR, United Kingdom
| | - Ana Cvejic
- Department of Haematology, University of Cambridge, Addenbrookes Hospital, Cambridge CB2 0XY, United Kingdom;
- Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
- Wellcome Trust-Medical Research Council Cambridge Stem Cell Institute, Cambridge CB2 1QR, United Kingdom
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