title: Simultaneous loss of beta- and gamma-catenin does not perturb hematopoiesis or lymphopoiesis.
abstract: Hematopietic stem cells (HSCs) maintain life-long hematopoiesis in the bone marrow via their ability to self-renew and to differentiate into all blood lineages. Although a central role for the canonical wnt signaling pathway has been suggested in HSC self-renewal as well as in the development of B and T cells, conditional deletion of beta-catenin (which is considered to be essential for Wnt signaling) has no effect on hematopoiesis or lymphopoiesis. Here, we address whether this discrepancy can be explained by a redundant and compensatory function of gamma-catenin, a close homolog of beta-catenin. Unexpectedly, we find that combined deficiency of beta- and gamma-catenin in hematopoietic progenitors does not impair their ability to self-renew and to reconstitute all myeloid, erythroid, and lymphoid lineages, even in competitive mixed chimeras and serial transplantations. These results exclude an essential role for canonical Wnt signaling (as mediated by beta- and/or gamma-catenin) during hematopoiesis and lymphopoiesis.
authors.affiliation: Swiss Institute for Experimental Cancer Research (ISREC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Epalinges, Switzerland.
authors.forename: Ute
authors.initials: U
authors.lastname: Koch
authors.forename: Anne
authors.initials: A
authors.lastname: Wilson
authors.forename: Monica
authors.initials: M
authors.lastname: Cobas
authors.forename: Rolf
authors.initials: R
authors.lastname: Kemler
authors.forename: H Robson
authors.initials: HR
authors.lastname: Macdonald
authors.forename: Freddy
authors.initials: F
authors.lastname: Radtke
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology; D016026:Bone Marrow Transplantation; D002678:Chimera; D005260:Female; D006410:Hematopoiesis / Q000502:physiology*; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000502:physiology*; D038041:Lymphopoiesis / Q000502:physiology*; D008297:Male; D051379:Mice; D008817:Mice, Mutant Strains; D011247:Pregnancy; D013601:T-Lymphocytes / Q000166:cytology; D051176:beta Catenin / Q000235:genetics* / Q000378:metabolism; D051185:gamma Catenin / Q000235:genetics* / Q000378:metabolism
chemical_list: C495267:CTNNB1 protein, mouse; D051176:beta Catenin; D051185:gamma Catenin