Date of Award
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Bachelor of Arts
Bradley Justin Davidson
In bilateral organisms, the development of the left- right axis follows a conserved model. Although the steps of LR axial patterning are well established many mechanisms facilitating LR patterning remain poorly characterized. It is known that Nodal and ion flux signaling are necessary for the establishment of the LR asymmetric morphogenesis yet, it is unknown how these initial signaling pathways impact laterally asymmetric gene expression. Here we show how the model organism Ciona robusta can be utilized to visualize asymmetric gene expression as well as how gene expression is affected by early symmetry breaking mechanisms, Nodal and ion flux. In our research, asymmetric gene expression within Ciona, previously established by TOMOseq, was visualized with in situ hybridization. To explore the impact of Nodal and ion flux on asymmetric gene expression embryos were treated with Nodal and ion flux inhibitors and underwent in situ hybridization using genes previously identified as asymmetrically enriched. Through this process we found that our data was highly variable due to dechorionization. This being said, the research demonstrated that asymmetric gene expression is primarily localized in the mesenchyme, and trunk lateral cell lineages. I also observed interesting changes in the expression patterns of Crkl, Klhl4, FoxC, and Mef2 following inhibitor treatments.
Tumey, Cameron R. , '21, "Exploration of Left-Right Asymmetric Gene Expression within Ciona robusta" (2021). Senior Theses, Projects, and Awards. 169.