Abstract
The Runx1/AML1 transcription factor is required for the generation of hematopoietic stem cells and is one of the most frequently targeted genes in human leukemia. Runx1-deficient mice die around embryonic day (E)12.5 due to severe hemorrhage in the central nervous system and the complete absence of definitive hematopoietic cells. Since mice lacking the heterodimeric partner of Runx1, PEBP2β/CBFβ, are almost identical in phenotype to Runx1 −/− mice, PEBP2β was believed to be essential for the in vivo function of Runx1. Here we show that transgenic overexpression of Runx1 partially rescues the lethal phenotype of PEBP2β-deficient mice at E12.5. Some of the rescued mice escaped from the severe hemorrhage at E11.5-12.5, although definitive hematopoiesis was not restored. Thus, PEBP2β-independent Runx1 activation can occur in vivo. This observation sheds new light on the mechanism(s) that regulate the activity of Runx transcription factors.
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References
Ito Y. Molecular basis of tissue-specific gene expression mediated by the runt domain transcription factor PEBP2/CBF. Genes Cells. 1999;4:685–96.
Adya N, Castilla LH, Liu PP. Function of CBFβ/Bro proteins. Semin Cell Dev Biol. 2000;11:361–8.
Speck NA, Gilliland DG. Core-binding factors in haematopoiesis and leukaemia. Nat Rev Cancer. 2002;2:502–3.
Osato M. Point mutations in the RUNX1/AML1 gene: another actor in RUNX leukemia. Oncogene. 2004;23:4284–96.
Cai ZL, de Bruijn M, Ma XQ, et al. Haploinsufficiency of AML1 affects the temporal and spatial generation of hematopoietic stem cells in the mouse embryo. Immunity. 2000;13:423–31.
Okada H, Watanabe T, Niki M, et al. AML1(-/-) embryos do not express certain hematopoiesis-related gene transcripts including those of the PU.1 gene. Oncogene. 1998;17:2287–93.
Okuda T, van Deursen J, Hiebert SW, Grosveld G, Downing JR. AML1, the target of multiple chromosomal translocations in human leukemia, is essential for normal fetal liver hematopoiesis. Cell. 1996;84:321–30.
Wang Q, Stacy T, Binder M, Marin Padilla M, Sharpe AH, Speck NA. Disruption of the Cbfa2 gene causes necrosis and hemorrhaging in the central nervous system and blocks definitive hematopoiesis. Proc Natl Acad Sci USA. 1996;93:3444–9.
Niki M, Okada H, Takano H, et al. Hematopoiesis in the fetal liver is impaired by targeted mutagenesis of a gene encoding a non-DNA binding subunit of the transcription factor, polyomavirus enhancer binding protein 2/core binding factor. Proc Natl Acad Sci USA. 1997;94:5697–702.
Sasaki K, Yagi H, Bronson RT, et al. Absence of fetal liver hematopoiesis in mice deficient in transcriptional coactivator core binding factor β. Proc Natl Acad Sci USA. 1996;93:12359–63.
Wang Q, Stacy T, Miller JD, et al. The CBFβ subunit is essential for CBFα2 (AML1) function in vivo. Cell. 1996;87:697–708.
Tahirov TH, Inoue-Bungo T, Morii H, et al. Structural analyses of DNA recognition by the AML1/Runx-1 Runt domain and its allosteric control by CBFβ. Cell. 2001;104:755–67.
Tang YY, Crute BE, Kelley JJ, et al. Biophysical characterization of interactions between the core binding factor alpha and beta subunits and DNA. FEBS Lett. 2000;470:167–72.
Kim WY, Sieweke M, Ogawa E, et al. Mutual activation of Ets-1 and AML1 DNA binding by direct interaction of their autoinhibitory domains. EMBO J. 1999;18:1609–20.
Thirunavukkarasu K, Mahajan M, McLarren KW, Stifani S, Karsenty G. Two domains unique to osteoblast-specific transcription factor Osf2/Cbfa1 contribute to its transactivation function and its inability to heterodimerize with Cbfβ. Mol Cell Biol. 1998;18:4197–208.
Yokomizo T, Takahashi S, Mochizuki N, et al. Characterization of GATA-1+ hemangioblastic cells in the mouse embryo. EMBO J. 2007;26:184–96.
Takakura N, Yoshida H, Ogura Y, Kataoka H, Nishikawa S, Nishikawa SI. PDGFRα expression during mouse embryogenesis: immunolocalization analyzed by whole-mount immunohistostaining using the monoclonal anti-mouse PDGFRα antibody APA5. J Histochem Cytochem. 1997;45:883–93.
Yokomizo T, Ogawa M, Osato M, et al. Requirement of Runx1/AML1/PEBP2αB for the generation of haematopoietic cells from endothelial cells. Genes Cells. 2001;6(1):13–23.
Huang G, Shigesada K, Ito K, Wee HJ, Yokomizo T, Ito Y. Dimerization with PEBP2β protects RUNX1/AML1 from ubiquitin-proteasome-mediated degradation. EMBO J. 2001;20:723–33.
Lacaud G, Gore L, Kennedy M, et al. Runx1 is essential for hematopoietic commitment at the hemangioblast stage of development in vitro. Blood. 2002;100:458–66.
Drissen R, von Lindern M, Kolbus A, et al. The erythroid phenotype of EKLF-null mice: defects in hemoglobin metabolism and membrane stability. Mol Cell Biol. 2005;25:5205–14.
Shimizu R, Takahashi S, Ohneda K, Engel JD, Yamamoto M. In vivo requirements for GATA-1 functional domains during primitive and definitive erythropoiesis. EMBO J. 2001;20:5250–60.
Miller J, Horner A, Stacy T, et al. The core-binding factor β subunit is required for bone formation and hematopoietic maturation. Nat Genet. 2002;32:645–9.
Takakura N, Watanabe T, Suenobu S, et al. A role for hematopoietic stem cells in promoting angiogenesis. Cell. 2000;102:199–209.
Samokhvalov IM, Samokhvalova NI, Nishikawa S. Cell tracing shows the contribution of the yolk sac to adult haematopoiesis. Nature. 2007;446:1056–61.
Lee J, Ahnn J, Bae SC. Homolog of RUNX and CBFβ/PEBP2β in C. elegans. Oncogene. 2004;23:4346–52.
Bollerot K, Romero S, Dunon D, Jaffredo T. Core binding factor in the early avian embryo: cloning of Cbfβ and combinatorial expression patterns with Runx1. Gene Expr Patterns. 2005;6:29–39.
Acknowledgments
We would like to thank Dr. K. Shigesada for helpful discussions.
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This work was supported by JST-ERATO, the Ministry of Education, Culture, Sports, Science and Technology, Japan, a Grant-in aid for Scientific research on Priority Areas, Japan, and A*STAR (Agency for Science, Technology and Research), Singapore.
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Yokomizo, T., Yanagida, M., Huang, G. et al. Genetic evidence of PEBP2β-independent activation of Runx1 in the murine embryo. Int J Hematol 88, 134–138 (2008). https://doi.org/10.1007/s12185-008-0121-4
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DOI: https://doi.org/10.1007/s12185-008-0121-4