title: ROCK inhibition abolishes the establishment of the aquiferous system in Ephydatia muelleri (Porifera, Demospongiae).
abstract: The Rho associated coiled-coil protein kinase (ROCK) plays crucial roles in development across bilaterian animals. The fact that the Rho/Rock pathway is required to initiate epithelial morphogenesis and thus to establish body plans in bilaterians makes this conserved signaling pathway key for studying the molecular mechanisms that may control early development of basally branching metazoans. The purpose of this study was to evaluate whether or not the main components of this signaling pathway exist in sponges, and if present, to investigate the possible role of the regulatory network in an early branching non-bilaterian species by evaluating ROCK function during Ephydatia muelleri development. Molecular phylogenetic analyses and protein domain predictions revealed the existence of Rho/Rock components in all studied poriferan lineages. Binding assays revealed that both Y-27632 and GSK429286A are capable of inhibiting Em-ROCK activity in vitro. Treatment with both drugs leads to impairment of growth and formation of the basal pinacoderm layer in the developing sponge. Furthermore, inhibition of Em-Rock prevents the establishment of a functional aquiferous system, including the absence of an osculum. In contrast, no effect of ROCK inhibition was observed in juvenile sponges that already possess a fully developed and functional aquiferous system. Thus, the Rho/Rock pathway appears to be essential for the proper development of the freshwater sponge, and may play a role in various cell behaviors (e.g. cell proliferation, cell adhesion and cell motility). Taken together, these data are consistent with an ancestral function of Rho/Rock signaling in playing roles in early developmental processes and may provide a new framework to study the interaction between Wnt signaling and the Rho/Rock pathway.
authors.affiliation: Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale (IMBE) - UMR CNRS 7263- IRD 237 - UAPV, Aix-Marseille Université, Marseille, France; Department of Genetics and Evolution, Institute of Genetics and Genomics in Geneva (IGe3), Faculty of Sciences, University of Geneva, Switzerland. Electronic address: quentin.schenkelaars@unige.ch.
authors.forename: Quentin
authors.initials: Q
authors.lastname: Schenkelaars
authors.affiliation: Department of Biology, University of Richmond, Richmond, VA 23173, USA.
authors.forename: Omar
authors.initials: O
authors.lastname: Quintero
authors.affiliation: Department of Biology, University of Richmond, Richmond, VA 23173, USA.
authors.forename: Chelsea
authors.initials: C
authors.lastname: Hall
authors.affiliation: Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale (IMBE) - UMR CNRS 7263- IRD 237 - UAPV, Aix-Marseille Université, Marseille, France.
authors.forename: Laura
authors.initials: L
authors.lastname: Fierro-Constain
authors.affiliation: Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale (IMBE) - UMR CNRS 7263- IRD 237 - UAPV, Aix-Marseille Université, Marseille, France.
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Renard
authors.affiliation: Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale (IMBE) - UMR CNRS 7263- IRD 237 - UAPV, Aix-Marseille Université, Marseille, France.
authors.forename: Carole
authors.initials: C
authors.lastname: Borchiellini
authors.affiliation: Department of Biology, University of Richmond, Richmond, VA 23173, USA. Electronic address: ahill2@richmond.edu.
authors.forename: April L
authors.initials: AL
authors.lastname: Hill
mesh_terms: D000577:Amides / Q000494:pharmacology; D000818:Animals; D004591:Electrophoresis, Polyacrylamide Gel; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D007191:Indazoles / Q000494:pharmacology; D009024:Morphogenesis / Q000187:drug effects* / Q000235:genetics; D009536:Niacinamide / Q000031:analogs & derivatives / Q000494:pharmacology; D010802:Phylogeny; D011161:Porifera / Q000145:classification / Q000235:genetics / Q000254:growth & development*; D047428:Protein Kinase Inhibitors / Q000494:pharmacology*; D011725:Pyridines / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013045:Species Specificity; D054460:rho-Associated Kinases / Q000037:antagonists & inhibitors* / Q000145:classification / Q000235:genetics
chemical_list: C584554:4-(4-(trifluoromethyl)phenyl)-N-(6-fluoro-1H-indazol-5-yl)-2-methyl-6-oxo-1,4,5,6-tetrahydro-3-pyridinecarboxamide; D000577:Amides; D007191:Indazoles; D047428:Protein Kinase Inhibitors; D011725:Pyridines; C108830:Y 27632; D009536:Niacinamide; D054460:rho-Associated Kinases
keywords: Development; Ephydatia muelleri; GSK429286A; Morphogenesis; Porifera; ROCK; Y-27632