title: Early myeloid lineage choice is not initiated by random PU.1 to GATA1 protein ratios.
abstract: The mechanisms underlying haematopoietic lineage decisions remain disputed. Lineage-affiliated transcription factors with the capacity for lineage reprogramming, positive auto-regulation and mutual inhibition have been described as being expressed in uncommitted cell populations. This led to the assumption that lineage choice is cell-intrinsically initiated and determined by stochastic switches of randomly fluctuating cross-antagonistic transcription factors. However, this hypothesis was developed on the basis of RNA expression data from snapshot and/or population-averaged analyses. Alternative models of lineage choice therefore cannot be excluded. Here we use novel reporter mouse lines and live imaging for continuous single-cell long-term quantification of the transcription factors GATA1 and PU.1 (also known as SPI1). We analyse individual haematopoietic stem cells throughout differentiation into megakaryocytic-erythroid and granulocytic-monocytic lineages. The observed expression dynamics are incompatible with the assumption that stochastic switching between PU.1 and GATA1 precedes and initiates megakaryocytic-erythroid versus granulocytic-monocytic lineage decision-making. Rather, our findings suggest that these transcription factors are only executing and reinforcing lineage choice once made. These results challenge the current prevailing model of early myeloid lineage choice.
authors.affiliation: Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland.|Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany.
authors.forename: Philipp S
authors.initials: PS
authors.lastname: Hoppe
authors.affiliation: Institute of Computational Biology, Helmholtz Zentrum München, 85764 Neuherberg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Schwarzfischer
authors.affiliation: Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland.|Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Loeffler
authors.affiliation: Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland.|Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany.
authors.forename: Konstantinos D
authors.initials: KD
authors.lastname: Kokkaliaris
authors.affiliation: Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland.|Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany.|Institute of Computational Biology, Helmholtz Zentrum München, 85764 Neuherberg, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Hilsenbeck
authors.affiliation: Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany.
authors.forename: Nadine
authors.initials: N
authors.lastname: Moritz
authors.affiliation: Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland.|Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany.
authors.forename: Max
authors.initials: M
authors.lastname: Endele
authors.affiliation: Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany.
authors.forename: Adam
authors.initials: A
authors.lastname: Filipczyk
authors.affiliation: MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK.
authors.forename: Adriana
authors.initials: A
authors.lastname: Gambardella
authors.affiliation: Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland.
authors.forename: Nouraiz
authors.initials: N
authors.lastname: Ahmed
authors.affiliation: Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland.
authors.forename: Martin
authors.initials: M
authors.lastname: Etzrodt
authors.affiliation: Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland.
authors.forename: Daniel L
authors.initials: DL
authors.lastname: Coutu
authors.affiliation: Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Rieger
authors.affiliation: Institute of Computational Biology, Helmholtz Zentrum München, 85764 Neuherberg, Germany.
authors.forename: Carsten
authors.initials: C
authors.lastname: Marr
authors.affiliation: Institute of Computational Biology, Helmholtz Zentrum München, 85764 Neuherberg, Germany.
authors.forename: Michael K
authors.initials: MK
authors.lastname: Strasser
authors.affiliation: Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Schauberger
authors.affiliation: Institute of Diabetes and Regeneration Research, Institute of Stem Cell Research, Helmholtz Zentrum München, Business Campus Garching, 85748 Garching, Germany.
authors.forename: Ingo
authors.initials: I
authors.lastname: Burtscher
authors.affiliation: Istituto di Biologia Cellulare e Neurobiologia, CNR, 00015 Monterotondo, Italy.
authors.forename: Olga
authors.initials: O
authors.lastname: Ermakova
authors.affiliation: Institute of Developmental Genetics, Helmholtz Zentrum München, 85764 Neuherberg, Germany.
authors.forename: Antje
authors.initials: A
authors.lastname: Bürger
authors.affiliation: Institute of Diabetes and Regeneration Research, Institute of Stem Cell Research, Helmholtz Zentrum München, Business Campus Garching, 85748 Garching, Germany.|Beta Cell Biology, Medical Faculty, Technical University Munich (TUM), 80333 Munich, Germany.
authors.forename: Heiko
authors.initials: H
authors.lastname: Lickert
authors.affiliation: MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK.|EMBL Mouse Biology Unit, 00015 Monterotondo, Italy.
authors.forename: Claus
authors.initials: C
authors.lastname: Nerlov
authors.affiliation: Institute of Computational Biology, Helmholtz Zentrum München, 85764 Neuherberg, Germany.|Department of Mathematics, Technical University Munich, 85748 Garching, Germany.
authors.forename: Fabian J
authors.initials: FJ
authors.lastname: Theis
authors.affiliation: Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland.|Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany.
authors.forename: Timm
authors.initials: T
authors.lastname: Schroeder
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D019070:Cell Lineage; D004912:Erythrocytes / Q000166:cytology; D025461:Feedback, Physiological; D005260:Female; D050982:GATA1 Transcription Factor / Q000378:metabolism*; D017930:Genes, Reporter; D006098:Granulocytes / Q000166:cytology; D006410:Hematopoiesis; D006412:Hematopoietic Stem Cells / Q000166:cytology; D008297:Male; D008533:Megakaryocytes / Q000166:cytology; D051379:Mice; D008954:Models, Biological; D009000:Monocytes / Q000166:cytology; D022423:Myeloid Cells / Q000166:cytology*; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D015203:Reproducibility of Results; D059010:Single-Cell Analysis; D013269:Stochastic Processes; D015534:Trans-Activators / Q000378:metabolism*; D000099232:Proto-Oncogene Protein Spi-1
chemical_list: D050982:GATA1 Transcription Factor; D011518:Proto-Oncogene Proteins; D015534:Trans-Activators; D000099232:Proto-Oncogene Protein Spi-1; C494689:Gata1 protein, mouse