A temporal coordination between Nodal and Wnt signalling governs the emergence of the
mammalian body plan
André Dias, Pau Pascual-Mas, Gabriel Torregrosa-Cortés, Harold M. McNamara, Alexandra E. Wehmeyer, Sebastian J. Arnold and Alfonso Martinez Arias
This weeks #FridayRead explores the role of Nodal and Wnt signaling in mammalian body patterning during gastrulation.
Wnt proteins are a large family of secreted glycoproteins which bind to the Fz receptor and regulate cell fate determination and neural patterning during embryonic development.
Wnt ligand binding activates two major signaling pathways, the non-canonical pathway, which is β-catenin-independent regulates cell polarity, migration and stem cell maintenance. The canonical pathway is Wnt/β-catenin dependent and is critical for embryonic development and homeostasis in adult tissues. CHIR99021, a glycogen synthase kinase (GSK) 3 inhibitor activat the Wnt/β-catenin signaling pathway.
Nodal is a TGF-β superfamily protein essential for early embryo patterning and mesoderm/endoderm induction. Nodal binds to activin receptors and activin A can be used to activated the nodal signaling pathway which leads to Smad2 phosphorylation. Nodal signaling also has role in maintenance of embryonic stem cell pluripotency.
Dias et al use stem cell based gastruloids to manipulate the Nodal and Wnt/β-catenin signaling and study the anterior/posterior cell fate induced. They found that induction of the Nodal pathway using activin A modified the primitive streak fate compared to CHIR99021 activation of the Wnt/β-catenin pathway.
They use these results to suggest Nodal is responsible for anterior fates and Wnt posterior fates in the development of the mammalian embryonic body plan.
This publication used Qkine activin A PLUS™ at 100 ng/ml or 25 ng/ml to activate Nodal signaling and alter the phenotype of the gastruloids.
