Planar cell polarization requires Widerborst, a B' regulatory subunit of protein phosphatase 2A.
We have identified widerborst (wdb), a B' regulatory subunit of PP2A, as a conserved component of planar cell polarization mechanisms in both Drosophila and in zebrafish. In Drosophila, wdb acts at two steps during planar polarization of wing epithelial cells. It is required to organize tissue polarity proteins into proximal and distal cortical domains, thus determining wing hair orientation. It is also needed to generate the polarized membrane outgrowth that becomes the wing hair. Widerborst activates the catalytic subunit of PP2A and localizes to the distal side of a planar microtubule web that lies at the level of apical cell junctions. This suggests that polarized PP2A activation along the planar microtubule web is important for planar polarization. In zebrafish, two wdb homologs are required for convergent extension during gastrulation, supporting the conjecture that Drosophila planar cell polarization and vertebrate gastrulation movements are regulated by similar mechanisms.
Hannus
Michael
M
Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse-108, 01307 Dresden, Germany.
Feiguin
Fabian
F
Heisenberg
Carl-Philipp
CP
Eaton
Suzanne
S
D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D019521:Body Patterning / Q000235:genetics / Q000502:physiology; D015820:Cadherins / Q000235:genetics; D016764:Cell Polarity / Q000235:genetics / Q000502:physiology; D000072261:Dishevelled Proteins; D004330:Drosophila / Q000166:cytology / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development*; D029721:Drosophila Proteins / Q000235:genetics / Q000502:physiology*; D005260:Female; D051157:Frizzled Receptors; D005775:Gastrula / Q000201:enzymology; D017344:Genes, Insect; D006197:Hair / Q000254:growth & development; D008297:Male; D008565:Membrane Proteins / Q000235:genetics; D008870:Microtubules / Q000201:enzymology; D009154:Mutation; D010641:Phenotype; D010750:Phosphoproteins / Q000235:genetics; D054648:Protein Phosphatase 2 / Q000235:genetics / Q000502:physiology*; D043562:Receptors, G-Protein-Coupled; D014921:Wings, Animal / Q000166:cytology / Q000254:growth & development; D015027:Zebrafish / Q000196:embryology* / Q000235:genetics / Q000378:metabolism*
D048868:Adaptor Proteins, Signal Transducing; D015820:Cadherins; D000072261:Dishevelled Proteins; D029721:Drosophila Proteins; D051157:Frizzled Receptors; D008565:Membrane Proteins; D010750:Phosphoproteins; D043562:Receptors, G-Protein-Coupled; C415248:S protein, Drosophila; C000603936:Wdb protein, Drosophila; C058784:fz protein, Drosophila; C121420:stan protein, Drosophila; D054648:Protein Phosphatase 2