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Date of Graduation
5-2027
Description
The notch signaling pathway is deeply conserved across animals from humans to sponges. It functions through direct cell-to-cell communication, where ligand binding triggers the cleavage of the Notch receptor’s intracellular domain (NICD), which then translocates to the nucleus to regulate transcription. In bilaterian lineages—animals with bilateral symmetry— Notch signaling is known to regulate binary cell fate decisions in diverse contexts ranging from neurogenesis to cancer. However, the functions of Notch signaling in early-branching animals, including cnidarians (e.g. jellyfish, corals and sea anemones), are still not fully understood; consequently, evolutionarily ancient roles of Notch remain ill-defined. To address this fundamental knowledge gap, we examine the role of the Notch receptor in Cnidaria, using the genetically tractable sea anemone cnidarian model Nematostella vectensis. By performing immunostaining of gastrula embryos with an antibody against the Notch intracellular domain, together with cell proliferation assays, we observed localization of the Notch intracellular domain in mitotic figures, but not in S-phase nuclei, in ectodermal and endodermal epithelia, indicating that Notch is activated in mitotic cells and may have a role in regulating mitosis. To further test this role, we used CRISPR/Cas9-mediated mutagenesis, to generate loss-of-function alleles of the Notch gene and confirmed successful mutations through genotyping PCR. We observed that early Notch mutant gastrula embryos had a higher number of ectodermal epithelial cells with enlarged nuclei than control embryos, consistent with Notch being necessary for cell division. Our preliminary data raise the possibility that Notch has an evolutionarily early role in controlling proliferative cellular states in animals.
Publication Date
2026
Document Type
Book
Degree Name
Bachelor of Science in Biology
Degree Level
Undergraduate
Department
Biological Sciences
Advisor/Mentor
Nakanishi, Nagayasu
Disciplines
Biology
Keywords
Natural Science
Citation
Norris, P. (2026). Moving towards defining the evolutionarily ancient role of notch signaling in animals.. 2026 Research Poster Competition. Retrieved from https://scholarworks.uark.edu/hnrcsturpc26/13
