RRC ID 30440
Author Oda H, Tsukita S.
Title Real-time imaging of cell-cell adherens junctions reveals that Drosophila mesoderm invagination begins with two phases of apical constriction of cells.
Journal J Cell Sci
Abstract Invagination of the epithelial cell sheet of the prospective mesoderm in Drosophila gastrulation is a well-studied, relatively simple morphogenetic event that results from dynamic cell shape changes and cell movements. However, these cell behaviors have not been followed at a sufficiently short time resolution. We examined mesoderm invagination in living wild-type embryos by real-time imaging of fluorescently labeled cell-cell adherens junctions, which are located at the apical zones of cell-cell contact. Low-light fluorescence video microscopy directly visualized the onset and progression of invagination. In an initial period of approximately 2 minutes, cells around the ventral midline reduced their apical surface areas slowly in a rather synchronous manner. Next, the central and more lateral cells stochastically accelerated or initiated their apical constriction, giving rise to random arrangements of cells with small and relatively large apices. Thus, we found that mesoderm invagination began with slow synchronous and subsequent fast stochastic phases of cell apex constriction. Furthermore, we showed that the mesoderm invagination of folded gastrulation mutant embryos lacked the normal two constriction phases, and instead began with asynchronous, feeble cell shape changes. Our observations suggested that Folded gastrulation-mediated signaling enabled synchronous activation of the contractile cortex, causing competition among the individual mesodermal cells for apical constriction. Movies available on-line: http://www.biologists.com/JCS/movies/jcs2073.html
Volume 114(Pt 3)
Pages 493-501
Published 2001-2-1
DOI 10.1242/jcs.114.3.493
PMID 11171319
MeSH Animals Cadherins / metabolism Cell Adhesion* Drosophila melanogaster / embryology* Drosophila melanogaster / genetics Gap Junctions* Green Fluorescent Proteins Luminescent Proteins / metabolism Mesoderm / cytology* Mesoderm / metabolism Mutation Ubiquitins / metabolism
IF 4.573
Times Cited 172
Drosophila DGRC#109007