beta-Catenin signals regulate cell growth and the balance between progenitor cell expansion and differentiation in the nervous system.
beta-Catenin is an essential component of the canonical Wnt signaling system that controls decisive steps in development. We employed here two conditional beta-catenin mutant alleles to alter beta-catenin signaling in the central nervous system of mice: one allele to ablate beta-catenin and the second allele to express a constitutively active beta-catenin. The tissue mass of the spinal cord and brain is reduced after ablation of beta-catenin, and the neuronal precursor population is not maintained. In contrast, the spinal cord and brain of mice that express activated beta-catenin is much enlarged in mass, and the neuronal precursor population is increased in size. beta-Catenin signals are thus essential for the maintenance of proliferation of neuronal progenitors, controlling the size of the progenitor pool, and impinging on the decision of neuronal progenitors to proliferate or to differentiate.
Zechner
Dietmar
D
Max-Delbrück-Center of Molecular Medicine, Robert-Rössle-Str. 10, 13125, Berlin, Germany.
Fujita
Yasuyuki
Y
Hülsken
Jörg
J
Müller
Thomas
T
Walther
Ingrid
I
Taketo
Makoto M
MM
Crenshaw
E Bryan
EB
Birchmeier
Walter
W
Birchmeier
Carmen
C
D000483:Alleles; D000818:Animals; D060466:Axin Protein; D001921:Brain / Q000166:cytology / Q000196:embryology / Q000378:metabolism; D001973:Bromodeoxyuridine / Q000378:metabolism; D002454:Cell Differentiation; D002455:Cell Division; D002490:Central Nervous System / Q000166:cytology* / Q000196:embryology* / Q000378:metabolism; D003598:Cytoskeletal Proteins / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D051379:Mice; D008817:Mice, Mutant Strains; D008822:Mice, Transgenic; D009154:Mutation; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D015398:Signal Transduction; D013116:Spinal Cord / Q000166:cytology / Q000196:embryology / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism; D015534:Trans-Activators / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D051153:Wnt Proteins; D029961:Zebrafish Proteins; D051176:beta Catenin
D060466:Axin Protein; C111729:Axin2 protein, mouse; C495267:CTNNB1 protein, mouse; D003598:Cytoskeletal Proteins; D011518:Proto-Oncogene Proteins; D015534:Trans-Activators; D051153:Wnt Proteins; D029961:Zebrafish Proteins; D051176:beta Catenin; D001973:Bromodeoxyuridine