RESUMO
During Caenorhabditis elegans vulval development, a signal from the anchor cell stimulates the RTK/RAS/MAPK (receptor tyrosine kinase/RAS/mitogen-activated protein kinase) signaling pathway in the closest vulval precursor cell P6.p to induce the primary fate. A lateral signal from P6.p then activates the Notch signaling pathway in the neighboring cells P5.p and P7.p to prevent them from adopting the primary fate and to specify the secondary fate. The MAP kinase phosphatase LIP-1 mediates this lateral inhibition of the primary fate. LIN-12/NOTCH up-regulates lip-1 transcription in P5.p and P7.p where LIP-1 inactivates the MAP kinase to inhibit primary fate specification. LIP-1 thus links the two signaling pathways to generate a pattern.
Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans/crescimento & desenvolvimento , Proteínas de Ciclo Celular , Proteínas de Helminto/metabolismo , Sistema de Sinalização das MAP Quinases , Proteínas de Membrana/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Fosfatases/genética , Proteínas Tirosina Fosfatases/metabolismo , Proteínas ras/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Padronização Corporal , Caenorhabditis elegans/citologia , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Domínio Catalítico , Feminino , Regulação da Expressão Gênica , Genes de Helmintos , Proteína Quinase 1 Ativada por Mitógeno , Dados de Sequência Molecular , Mutação , Estrutura Terciária de Proteína , Proteínas Tirosina Fosfatases/química , Receptores Proteína Tirosina Quinases/metabolismo , Receptores Notch , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais , Células-Tronco/citologia , Células-Tronco/metabolismo , Regulação para Cima , Vulva/citologia , Vulva/crescimento & desenvolvimentoRESUMO
Inactivation of the Caenorhabditis elegans APC-related gene (apr-1) has pointed at two separate functions of apr-1. First, apr-1 is required for the migration of epithelial cells during morphogenesis of the embryo. In this process, APR-1 may act in a Cadherin/alpha-Catenin/beta-Catenin complex as a component of adherens junctions. Second, apr-1 is required for Hox gene expression, most likely by positively regulating the activity of the Wingless signaling pathway. During embryogenesis, apr-1 is required for the expression of ceh-13 labial in anterior seam and muscle cells and during larval development, apr-1 is necessary for the expression of lin-39 deformed in the vulval precursor cells. Thus, APR-1 may positively regulate the activity of the beta-Catenin/Armadillo-related proteins HMP-2 in migrating epithelial cells and BAR-1 in the vulval precursor cells.
