Wnt signaling in the niche.
There is much interest in understanding the signals in the bone marrow niche that keep hematopoietic stem cells (HSCs) in a quiescent state. In the current issue of Cell Stem Cell, Fleming et al. (2008) report that blocking Wnt signaling in the niche increases the number of proliferating HSCs and reduces their ability to reconstitute the hematopoietic system of irradiated recipient mice. These findings show that Wnt/beta-catenin activity is crucial for the maintenance of HSC quiescence in the bone marrow niche.
Suda
Toshio
T
Department of Cell Differentiation, The Sakaguchi Laboratory of Developmental Biology, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582, Japan. sudato@sc.itc.keio.ac.jp
Arai
Fumio
F
D000818:Animals; D001853:Bone Marrow / Q000378:metabolism; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000378:metabolism*; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics; D051379:Mice; D008822:Mice, Transgenic; D010006:Osteoblasts / Q000378:metabolism; D051153:Wnt Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*
C501127:Dkk1 protein, mouse; D036341:Intercellular Signaling Peptides and Proteins; D051153:Wnt Proteins