Date of Award
2023
Document Type
Dissertation
Publication Status
Version of Record
Submission Date
October 2026
Thesis/Dissertation Advisor [Chair]
Murphey, Rodney
Abstract
Proper formation of synapses in the developing nervous system is critical to the expected function and behavior of an adult organism. Neurons must project neurites, in the form of axons or dendrites, to target areas to complete synaptic circuits. The biochemical tool that cells use to interact with the external environment and direct the guidance of developing neurites are guidance receptors. One such guidance receptor that is extensively studied to uncover its roles in developmental disorders and disease is DSCAM (Down-Syndrome Cell Adhesion Molecule). To better understand the role of DSCAM in humans, a fly homolog Dscam1 was extensively characterized in the giant fiber system (GFS) of Drosophila to further explore its roles in axon guidance, synapse formation, and synapse function. The UAS-Gal4 system was used to alter the protein levels of Dscam1 within the giant fiber interneurons (GFs). A UAS-RNAi construct against Dscam1 was used to knockdown translation of all possible isoforms within the GFs. A UAS-Dscam1(TM2) construct was used to overexpress a single isoform of Dscam1 that is specifically trafficked to the axons. Confocal microscopy was used to determine the morphological changes associated with dysregulated Dscam1 levels. Visualization via fluorescent markers was accomplished of both pre- and post-synaptic cells, the GFs and tergotrochanteral motorneurons (TTMns), respectively, and synapse interface was determined as colocalization of the two cells. Additionally, the functional components of the GF-TTMn synapse, both gap-junctions, and presynaptic chemical active zones were tagged via fluorescent antibodies and quantified.
Extent
116 p.
Recommended Citation
Spencer, Casey L., "Dscam1 Regulates Synapse Formation and Function in the Giant Fiber System of Drosophila" (2023). Electronic Theses and Dissertations 2020 - Present. 1156.
https://digitalcommons.fau.edu/etd_general/1156
Identifier
FA00014364
Comments
Includes bibliography.|Dissertation (PhD)--Florida Atlantic University, 2023.|FAU Electronic Theses and Dissertations Collection|Includes bibliography.