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Title: A novel protein Moat prevents ectopic epithelial folding by limiting Bazooka/Par3-dependent adherens junctions
Contractile myosin and cell adhesion work together to induce tissue shape changes, but how they are patterned to achieve diverse morphogenetic outcomes remains unclear. Epithelial folding occurs via apical constriction, mediated by apical contractile myosin engaged with adherens junctions, as in Drosophila ventral furrow formation. While it has been shown that a multicellular gradient of myosin contractility determines folding shape, the impact of multicellular patterning of adherens junction levels on tissue folding is unknown. We identified a novel Drosophila gene  moat essential for differential apical constriction and folding behaviors across the ventral epithelium which contains both folding ventral furrow and nonfolding ectodermal anterior midgut (ectoAMG). We show that Moat functions to downregulate polarity-dependent adherens junctions through inhibiting cortical clustering of Bazooka/Par3 proteins. Such downregulation of polarity-dependent junctions is critical for establishing a myosin-dependent pattern of adherens junctions, which in turn mediates differential apical constriction in the ventral epithelium. In  moat mutants, abnormally high levels of polarity-dependent junctions promote ectopic apical constriction in cells with low-level contractile myosin, resulting in expansion of infolding from ventral furrow to ectoAMG, and flattening of ventral furrow constriction gradient. Our results demonstrate that tissue-scale distribution of adhesion levels patterns apical constriction and establishes morphogenetic boundaries.  more » « less
Award ID(s):
2341010
PAR ID:
10591826
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Editor(s):
Wallingford, John
Publisher / Repository:
ASCB
Date Published:
Journal Name:
Molecular Biology of the Cell
Volume:
35
Issue:
8
ISSN:
1059-1524
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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