Date of Completion

2024

Thesis Type

College of Arts and Science Honors

Department

Biology

First Advisor

Bryan Ballif

Second Advisor

Alicia Ebert

Keywords

Semaphorin, Plexin, Development, Signaling, Zebrafish, Retina

Abstract

Semaphorins (Semas) are a large family of transmembrane proteins that play important roles in development, including aspects of cell migration, adhesion, proliferation, and differentiation (Alto & Terman, 2017). Plexins (Plxn) are the main functional receptors of Semas. When Sema binds to Plxn, this initiates forward signaling through the intracellular domain of Plxn, leading to downstream signaling cascades. Our lab uncovered a novel role for Sema6A/PlxnA2 signaling in zebrafish eye development specifically to maintain eye cohesion, however it is unknown which downstream signaling pathway(s) are used in this process (Ebert et al., 2014, St. Clair et al., 2018 & 2019). Preliminary data has hinted that both PlxnA2 and insulin share an intracellular signaling mechanism necessary for driving early eye field cohesion, as treating early zebrafish eye field explants with Sema6A or insulin results in proper eye field cohesion. In this project, I confirmed that insulin signaling maintains eye field cohesion similarly to Sema6A- PlxnA2 signaling. Additionally, I identified PI3K as one downstream intracellular signaling mechanism of both insulin and PlxnA2 responsible for maintaining eye cohesion in early zebrafish embryos.

Available for download on Saturday, May 09, 2026

Share

COinS