title: Laminin is required to orient epithelial polarity in the C. elegans pharynx.
abstract: The development of many animal organs involves a mesenchymal to epithelial transition, in which cells develop and coordinate polarity through largely unknown mechanisms. The C. elegans pharynx, which is an epithelial tube in which cells polarize around a central lumen, provides a simple system with which to understand the coordination of epithelial polarity. We show that cell fate regulators cause pharyngeal precursor cells to group into a bilaterally symmetric, rectangular array of cells called the double plate. The double plate cells polarize with apical localization of the PAR-3 protein complex, then undergo apical constriction to form a cylindrical cyst. We show that laminin, but not other basement membrane components, orients the polarity of the double plate cells. Our results provide in vivo evidence that laminin has an early role in cell polarity that can be distinguished from its later role in basement membrane integrity.
authors.affiliation: Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
authors.forename: Jeffrey P
authors.initials: JP
authors.lastname: Rasmussen
authors.forename: Sowmya Somashekar
authors.initials: SS
authors.lastname: Reddy
authors.forename: James R
authors.initials: JR
authors.lastname: Priess
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000196:embryology*; D029742:Caenorhabditis elegans Proteins / Q000378:metabolism*; D016764:Cell Polarity / Q000502:physiology*; D004847:Epithelial Cells / Q000502:physiology*; D005455:Fluorescent Antibody Technique; D007797:Laminin / Q000378:metabolism / Q000502:physiology*; D018613:Microscopy, Confocal; D010614:Pharynx / Q000166:cytology / Q000196:embryology*; D017346:Protein Serine-Threonine Kinases
chemical_list: D029742:Caenorhabditis elegans Proteins; D007797:Laminin; C097238:PAR-3 protein, C elegans; D017346:Protein Serine-Threonine Kinases