|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | |||||
Research Article |
Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, M5S 1A8 Canada
* Author for correspondence (e-mail: paul.hamel{at}utoronto.ca)
Accepted 26 October 2001
Mutations to Pax3 and other Pax family genes in both mice and humans result in numerous tissue-specific morphological defects. Little is known, however, about the cellular and molecular mechanisms by which Pax genes regulate morphogenesis. We previously showed that Pax3 induces cell aggregation and a mesenchymal-to-epithelial transition in Saos-2 cells. We show here that Pax3-induced aggregates arise through the formation of distinct structures involving cell rearrangements and cell behaviors resembling those that occur during gastrulation and neurulation known as convergent extension. During these Pax3-induced processes, Dishevelled and Frizzled are localized to the actin cytoskeleton and both proteins coimmunoprecipitate focal adhesion components from detergent-insoluble cell fractions. We show further that these Pax3-induced cell movements are associated with activation of a Wnt-signaling cascade, resulting in induction and activation of c-Jun-N-terminal kinase/stress activated protein kinase (JNK/SAPK). All of these Wnt-signaling factors exhibit altered subcellular distribution in Pax3-expressing cells. In particular, we show the localization of JNK/SAPK to both the nucleus and to cytoplasmic multi-vesicular structures. These data show that Pax3 regulates morphogenetic cell behavior and that regulation of a conserved, planar cell polarity/noncanonical Wnt-signaling cascade entailing JNK activation is a function of Pax3 activity.
Key words: Pax3, Wnt-signaling, Dishevelled, Focal adhesion, JNK, Frizzled
This article has been cited by other articles:
![]() |
S. Witzel, V. Zimyanin, F. Carreira-Barbosa, M. Tada, and C.-P. Heisenberg Wnt11 controls cell contact persistence by local accumulation of Frizzled 7 at the plasma membrane J. Cell Biol., December 4, 2006; 175(5): 791 - 802. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. B. Wallingford and R. Habas The developmental biology of Dishevelled: an enigmatic protein governing cell fate and cell polarity Development, October 15, 2005; 132(20): 4421 - 4436. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. B. Wallingford and R. M. Harland Neural tube closure requires Dishevelled-dependent convergent extension of the midline Development, March 14, 2003; 129(24): 5815 - 5825. [Abstract] [Full Text] [PDF] |
||||
![]() |
O'N. Wiggan, M. P. Fadel, and P. A. Hamel Pax3 induces cell aggregation and regulates phenotypic mesenchymal-epithelial interconversion J. Cell Sci., January 2, 2002; 115(3): 517 - 529. [Abstract] [Full Text] [PDF] |
||||