Antagonism of LIN-17/Frizzled and LIN-18/Ryk in nematode vulva induction reveals evolutionary alterations in core developmental pathways.

Most diversity in animals and plants results from the modification of already existing structures. Many organ systems, for example, are permanently modified during evolution to create developmental and morphological diversity, but little is known about the evolution of the underlying developmental m...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Xiaoyue Wang, Ralf J Sommer
Formato: article
Lenguaje:EN
Publicado: Public Library of Science (PLoS) 2011
Materias:
Acceso en línea:https://doaj.org/article/784cf008a0574c3d8aac088309dbbf6e
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
Descripción
Sumario:Most diversity in animals and plants results from the modification of already existing structures. Many organ systems, for example, are permanently modified during evolution to create developmental and morphological diversity, but little is known about the evolution of the underlying developmental mechanisms. The theory of developmental systems drift proposes that the development of conserved morphological structures can involve large-scale modifications in their regulatory mechanisms. We test this hypothesis by comparing vulva induction in two genetically tractable nematodes, Caenorhabditis elegans and Pristionchus pacificus. Previous work indicated that the vulva is induced by epidermal growth factor (EGF)/RAS and WNT signaling in Caenorhabditis and Pristionchus, respectively. Here, we show that the evolution of vulva induction involves major molecular alterations and that this shift of signaling pathways involves a novel wiring of WNT signaling and the acquisition of novel domains in otherwise conserved receptors in Pristionchus vulva induction. First, Ppa-LIN-17/Frizzled acts as an antagonist of WNT signaling and suppresses the ligand Ppa-EGL-20 by ligand sequestration. Second, Ppa-LIN-18/Ryk transmits WNT signaling and requires inhibitory SH3 domain binding motifs, unknown from Cel-LIN-18/Ryk. Third, Ppa-LIN-18/Ryk signaling involves Axin and β-catenin and Ppa-axl-1/Axin is epistatic to Ppa-lin-18/Ryk. These results confirm developmental system drift as an important theory for the evolution of organ systems and they highlight the significance of protein modularity in signal transduction and the dynamics of signaling networks.