title: Rho signaling pathway and apical constriction in the early lens placode.
abstract: Epithelial invagination in many model systems is driven by apical cell constriction, mediated by actin and myosin II contraction regulated by GTPase activity. Here we investigate apical constriction during chick lens placode invagination. Inhibition of actin polymerization and myosin II activity by cytochalasin D or blebbistatin prevents lens invagination. To further verify if lens placode invaginate through apical constriction, we analyzed the role of Rho-ROCK pathway. Rho GTPases expression at the apical portion of the lens placode occurs with the same dynamics as that of the cytoskeleton. Overexpression of the pan-Rho inhibitor C3 exotoxin abolished invagination and had a strong effect on apical myosin II enrichment and a mild effect on apical actin localization. In contrast, pharmacological inhibition of ROCK activity interfered significantly with apical enrichment of both actin and myosin. These results suggest that apical constriction in lens invagination involves ROCK but apical concentration of actin and myosin are regulated through different pathways upstream of ROCK. genesis 49:368-379, 2011.
authors.affiliation: Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Ricardo Moraes
authors.initials: RM
authors.lastname: Borges
authors.forename: Marcelo Lazzaron
authors.initials: ML
authors.lastname: Lamers
authors.forename: Fabio Luis
authors.initials: FL
authors.lastname: Forti
authors.forename: Marinilce Fagundes Dos
authors.initials: MF
authors.lastname: Santos
authors.forename: Chao Yun Irene
authors.initials: CY
authors.lastname: Yan
mesh_terms: D036002:ADP Ribose Transferases / Q000235:genetics / Q000378:metabolism; D000199:Actins / Q000378:metabolism; D000205:Actomyosin / Q000378:metabolism; D000577:Amides / Q000494:pharmacology; D000818:Animals; D001905:Botulinum Toxins / Q000235:genetics / Q000378:metabolism; D002642:Chick Embryo; D002645:Chickens; D015638:Cytochalasin D / Q000494:pharmacology; D003599:Cytoskeleton / Q000187:drug effects / Q000378:metabolism*; D004475:Ectoderm / Q000196:embryology / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D005455:Fluorescent Antibody Technique; D006576:Heterocyclic Compounds, 4 or More Rings / Q000494:pharmacology; D007150:Immunohistochemistry; D007908:Lens, Crystalline / Q000196:embryology / Q000378:metabolism*; D024462:Myosin Type II / Q000037:antagonists & inhibitors / Q000378:metabolism; D019384:Nucleic Acid Synthesis Inhibitors / Q000494:pharmacology; D011725:Pyridines / Q000494:pharmacology; D015398:Signal Transduction; D020741:rho GTP-Binding Proteins / Q000378:metabolism*; D054460:rho-Associated Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D000199:Actins; D000577:Amides; D004791:Enzyme Inhibitors; D006576:Heterocyclic Compounds, 4 or More Rings; D019384:Nucleic Acid Synthesis Inhibitors; D011725:Pyridines; C108830:Y 27632; C472645:blebbistatin; D015638:Cytochalasin D; D000205:Actomyosin; D036002:ADP Ribose Transferases; C063007:exoenzyme C3, Clostridium botulinum; D054460:rho-Associated Kinases; D001905:Botulinum Toxins; D024462:Myosin Type II; D020741:rho GTP-Binding Proteins