title: Normal hemopoiesis and lymphopoiesis in the combined absence of numb and numblike.
abstract: The mammalian ortholog of the conserved Drosophila adaptor protein Numb (Nb) and its homolog Numblike (Nbl) modulate neuronal cell fate determination at least in part by antagonizing Notch signaling. Because the Notch pathway has been implicated in regulating hemopoietic stem cell self-renewal and T cell fate specification in mammals, we investigated the role of Nb and Nbl in hemopoiesis using conditional gene targeting. Surprisingly simultaneous deletion of both Nb and Nbl in murine bone marrow precursors did not affect the ability of stem cells to self-renew or to give rise to differentiated myeloid or lymphoid progeny, even under competitive conditions in mixed chimeras. Furthermore, T cell fate specification and intrathymic T cell development were unaffected in the combined absence of Nb and Nbl. Collectively our data indicate that the Nb family of adaptor proteins is dispensable for hemopoiesis and lymphopoiesis in mice, despite their proposed role in neuronal stem cell development.
authors.affiliation: Ludwig Institute for Cancer Research, Lausanne Branch, University of Lausanne, Switzerland.
authors.forename: Anne
authors.initials: A
authors.lastname: Wilson
authors.forename: Denis-Luc
authors.initials: DL
authors.lastname: Ardiet
authors.forename: Catherine
authors.initials: C
authors.lastname: Saner
authors.forename: Nathalie
authors.initials: N
authors.lastname: Vilain
authors.forename: Friedrich
authors.initials: F
authors.lastname: Beermann
authors.forename: Michel
authors.initials: M
authors.lastname: Aguet
authors.forename: H Robson
authors.initials: HR
authors.lastname: Macdonald
authors.forename: Olav
authors.initials: O
authors.lastname: Zilian
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology; D019070:Cell Lineage / Q000235:genetics / Q000276:immunology; D006410:Hematopoiesis / Q000235:genetics / Q000276:immunology*; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D038041:Lymphopoiesis / Q000235:genetics / Q000276:immunology*; D008565:Membrane Proteins / Q000096:biosynthesis / Q000172:deficiency* / Q000235:genetics*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000172:deficiency* / Q000235:genetics*; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D013950:Thymus Gland / Q000166:cytology / Q000378:metabolism
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; C106293:Numb protein, mouse; C106292:Numbl protein, mouse