Asymmetric localization of a mammalian numb homolog during mouse cortical neurogenesis.
During Drosophila neurogenesis, differential segregation of Numb is necessary for daughter cells of asymmetric divisions to adopt distinct fates, at least partly by biasing the Notch-mediated cell-cell interaction. We have isolated a highly conserved mammalian homolog of Drosophila numb, m-numb. During mouse cortical neurogenesis, m-Numb is asymmetrically localized to the apical membrane of dividing ventricular neural progenitors. Depending upon the orientation of the cleavage plane, m-Numb may be distributed into one or both of the daughter cells. When expressed in Drosophila embryos, m-Numb is localized asymmetrically in dividing neural precursors and rescues the numb mutant phenotype. Furthermore, m-Numb can physically interact with mouse Notch1. We propose that some shared molecular mechanisms, both cell-intrinsic and cell-extrinsic, generate asymmetric cell divisions during neurogenesis of vertebrates and invertebrates.
Zhong
W
W
Howard Hughes Medical Institute, University of California, San Francisco 94143-0724, USA.
Feder
J N
JN
Jiang
M M
MM
Jan
L Y
LY
Jan
Y N
YN
D000595:Amino Acid Sequence; D000818:Animals; D002455:Cell Division; D002462:Cell Membrane / Q000378:metabolism; D002540:Cerebral Cortex / Q000166:cytology / Q000196:embryology* / Q000378:metabolism*; D004330:Drosophila; D029721:Drosophila Proteins; D004622:Embryo, Mammalian / Q000378:metabolism; D004625:Embryo, Nonmammalian; D005314:Embryonic and Fetal Development; D007605:Juvenile Hormones / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice / Q000196:embryology*; D008969:Molecular Sequence Data; D009154:Mutation; D009474:Neurons / Q000378:metabolism; D051381:Rats; D011956:Receptors, Cell Surface / Q000378:metabolism; D051880:Receptors, Notch; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution
D029721:Drosophila Proteins; D007605:Juvenile Hormones; D008565:Membrane Proteins; C497759:N protein, Drosophila; D011956:Receptors, Cell Surface; D051880:Receptors, Notch; C060606:numb protein, Drosophila