Distinct Rap1 activity states control the extent of epithelial invagination via α-catenin.

TitleDistinct Rap1 activity states control the extent of epithelial invagination via α-catenin.
Publication TypeJournal Articles
Year of Publication2013
AuthorsWang Y-C, Khan Z, Wieschaus EF
JournalDev Cell
Date Published2013 May 13
KeywordsActins, alpha Catenin, Animals, Cell Adhesion, Cell Adhesion Molecules, Cell Membrane, Cell Shape, Drosophila, Drosophila Proteins, Embryo, Nonmammalian, Enzyme Activation, Epithelial Cells, Genes, Insect, Green Fluorescent Proteins, GTP Phosphohydrolases, GTPase-Activating Proteins, Intercellular Junctions, RNA Interference, Time factors, Time-Lapse Imaging

Localized cell shape change initiates epithelial folding, while neighboring cell invagination determines the final depth of an epithelial fold. The mechanism that controls the extent of invagination remains unknown. During Drosophila gastrulation, a higher number of cells undergo invagination to form the deep posterior dorsal fold, whereas far fewer cells become incorporated into the initially very similar anterior dorsal fold. We find that a decrease in α-catenin activity causes the anterior fold to invaginate as extensively as the posterior fold. In contrast, constitutive activation of the small GTPase Rap1 restricts invagination of both dorsal folds in an α-catenin-dependent manner. Rap1 activity appears spatially modulated by Rapgap1, whose expression levels are high in the cells that flank the posterior fold but low in the anterior fold. We propose a model whereby distinct activity states of Rap1 modulate α-catenin-dependent coupling between junctions and actin to control the extent of epithelial invagination.

Alternate JournalDev. Cell
PubMed ID23623612
PubMed Central IDPMC3741050
Grant List5R37HD15587 / HD / NICHD NIH HHS / United States
R37 HD015587 / HD / NICHD NIH HHS / United States
/ / Howard Hughes Medical Institute / United States