Importance: Moyamoya disease (MMD), a progressive vasculopathy leading to narrowing and ultimate occlusion of the intracranial internal carotid arteries, is a cause of childhood stroke. The cause of MMD is poorly understood, but genetic factors play a role. Several familial forms of MMD have been identified, but the cause of most cases remains elusive, especially among non-East Asian individuals.
View Article and Find Full Text PDFDuring vertebrate gastrulation, convergence and extension movements elongate embryonic tissues anteroposteriorly and narrow them mediolaterally. Planar cell polarity (PCP) signaling is essential for mediolateral cell elongation underlying these movements, but how this polarity arises is poorly understood. We analyzed the elongation, orientation and migration behaviors of lateral mesodermal cells undergoing convergence and extension movements in wild-type zebrafish embryos and mutants for the Wnt/PCP core component Vangl2 (Trilobite).
View Article and Find Full Text PDFDuring vertebrate gastrulation, Wnt/planar cell polarity (PCP) signaling orchestrates polarized cell behaviors underlying convergence and extension (C&E) movements to narrow embryonic tissues mediolaterally and lengthen them anteroposteriorly. Here, we have identified Gpr125, an adhesion G protein-coupled receptor, as a novel modulator of the Wnt/PCP signaling system. Excess Gpr125 impaired C&E movements and the underlying cell and molecular polarities.
View Article and Find Full Text PDFPlanar cell polarization entails establishment of cellular asymmetries within the tissue plane. An evolutionarily conserved planar cell polarity (PCP) signaling system employs intra- and intercellular feedback interactions between its core components, including Frizzled, Van Gogh, Flamingo, Prickle, and Dishevelled, to establish their characteristic asymmetric intracellular distributions and coordinate planar polarity of cell populations. By translating global patterning information into asymmetries of cell membranes and intracellular organelles, PCP signaling coordinates morphogenetic behaviors of individual cells and cell populations with the embryonic polarity.
View Article and Find Full Text PDFVertebrate gastrulation entails massive cell movements that establish and shape the germ layers. During gastrulation, the individual cell behaviors are strictly coordinated in time and space by various signaling pathways. These pathways instruct the cells about proliferation, shape, fate and migration into proper location.
View Article and Find Full Text PDFThe antero-posterior dispersion of clonally related cells is a prominent feature of axis elongation in vertebrate embryos. Two major models have been proposed: (i) the intercalation of cells by convergent-extension and (ii) the sequential production of the forming axis by stem cells. The relative importance of both of these cell behaviors during the long period of elongation is poorly understood.
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