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Alternative Title

Visualizing bioelectric patterns and their relationship to axis determination in Danio rerio

Publication Date


First Advisor

Michael J.F. Barresi

Document Type

Honors Project

Degree Name

Bachelor of Arts




Bioelectrics, Embryonic development, Axis determination, Zebrafish, Transgenesis, Genetically encoded voltage indicators, Tol2 system, Gateway cloing system


Bioelectrics, or the different membrane potentials that exist across a tissue and whole organism, is emerging to be an important, yet understudied, mechanism that may influence a variety of developmental processes. Although evidence is mounting to support a role for bioelectric signaling during regeneration, much less research has been done to explore its involvement in the formation of an embryo. Our lab has begun an investigation into the roles that bioelectrics may play during early axis determination in the developing zebrafish embryo (Danio rerio). Using voltage sensitive dyes and transient expression of Genetically Encoded Voltage Indicators, we show here preliminary data suggesting that a gradient of differential membrane potentials does exist from the dorsal to ventral axis of the developing gastrula. Moreover, to monitor changes in bioelectric patterns over time, we are currently generating stable transgenic lines expressing different Genetically Encoded Voltage Indicators, namely ArcLight, Marina, and FlicR1, using the Tol2 Recombinational Cloning System. Future experiments that utilize these transgenic lines will be able to compare bioelectric patterns between existing zebrafish mutant lines, show how bioelectric patterns are established by various ion channels or gap junctions, and correlate the electrical signals to existing morphogen patterns. By characterizing the bioelectrics in wildtype embryos and quantifiably comparing them to altered embryos, we will be able to better understand how cells utilize both protein and electrical gradients to collaborate with their neighbors to create complex and highly organized body structures.


©2021 Elora Celine Greiner




50 pages : illustrations (chiefly color) Includes bibliographical references (pages 46-50)