The Caenorhabditis elegans gene lin-26 can trigger epithelial differentiation without conferring tissue specificity.
How epithelial cell fates become specified is poorly understood. We have previously shown that the putative C2H2 zinc-finger transcription factor LIN-26 is required for the differentiation of ectodermal and mesodermal epithelial cells in Caenorhabditis elegans. Here, we report that ectopic LIN-26 expression during early gastrulation transforms most blastomeres into epithelial-like cells. Specifically, LIN-26 induced the expression of three epithelial markers: the adherens junction protein JAM-1; DLG-1, which is essential for the assembly of JAM-1 at junctions; and CHE-14, which is involved in apical trafficking. Furthermore, ultrastructural studies revealed that ectopic LIN-26 expression induced the formation of adherens-like junctions. However, ectopic lin-26 expression did not confer any tissue-specific cell fate, such as the epidermal cell fate, as evidenced from the observation that several epidermal-specific genes were not induced. Conversely, we show that epidermal cells displayed some polarity defects in lin-26 mutants. We conclude that lin-26 can induce epithelial differentiation and that epitheliogenesis is not a default pathway in C. elegans.
Quintin
S
S
Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, F-67404 Illkirch Cedex, C.U. de Strasbourg, France.
Michaux
G
G
McMahon
L
L
Gansmuller
A
A
Labouesse
M
M
D000818:Animals; D030801:Animals, Genetically Modified; D001757:Blastomeres / Q000378:metabolism; D017173:Caenorhabditis elegans / Q000235:genetics*; D029742:Caenorhabditis elegans Proteins; D015815:Cell Adhesion Molecules; D002454:Cell Differentiation; D019070:Cell Lineage; D018076:DNA, Complementary / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics*; D029721:Drosophila Proteins; D004475:Ectoderm / Q000378:metabolism; D004625:Embryo, Nonmammalian / Q000648:ultrastructure; D004817:Epidermis / Q000196:embryology / Q000378:metabolism; D005775:Gastrula / Q000378:metabolism; D049452:Green Fluorescent Proteins; D006358:Hot Temperature; D019476:Insect Proteins / Q000378:metabolism; D008164:Luminescent Proteins / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D008648:Mesoderm / Q000378:metabolism; D008854:Microscopy, Electron; D008954:Models, Biological; D010641:Phenotype; D011956:Receptors, Cell Surface; D013696:Temperature; D014157:Transcription Factors / Q000235:genetics*; D025521:Tumor Suppressor Proteins
C441580:AJM-1 protein, C elegans; D029742:Caenorhabditis elegans Proteins; D015815:Cell Adhesion Molecules; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D019476:Insect Proteins; D008164:Luminescent Proteins; D008565:Membrane Proteins; D011956:Receptors, Cell Surface; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; C090507:lin-26 protein, C elegans; C070350:dlg1 protein, Drosophila; D049452:Green Fluorescent Proteins