Notch Signalling Under Maternal-to-Zygotic Transition

The development of all animal embryos is initially directed by the gene products supplied by their mothers. With the progression of embryogenesis, the embryo's genome is activated to command subsequent developments. This transition, which has been studied in many model animals, is referred to as the Maternal-to-Zygotic Transition (MZT). In many organisms, including flies, nematodes, and sea urchins, genes involved in Notch signaling are extensively influenced by the MZT. This signaling pathway is highly conserved across metazoans; moreover, it regulates various developmental processes. Notch signaling defects are commonly associated with various human diseases. The maternal contribution of its factors was first discovered in flies. Subsequently, several genes were identified from mutant embryos with a phenotype similar to Notch mutants only upon the removal of the maternal contributions. Studies on these maternal genes have revealed various novel steps in the cascade of Notch signal transduction. Among these genes, pecanex and almondex have been functionally characterized in recent studies. Therefore, in this review, we will focus on the roles of these two maternal genes in Notch signaling and discuss future research directions on its maternal function.

Automated summary

The development of animal embryos is initially directed by maternal gene products, transitioning to activation of the embryo's genome during the Maternal-to-Zygotic Transition (MZT). Genes involved in the highly conserved Notch signaling pathway are influenced by the MZT in various organisms and defects in this pathway are associated with human diseases. Studies on maternal gene contributions to Notch signaling have revealed novel steps in its signal transduction cascade, with genes like pecanex and almondex being functionally characterized in recent research.