Presenter(s): George Deardorff
Co Presenter(s): Bryson Ramona
Faculty Mentor(s): Kryn Stankunas & Scott Stewart
Poster 44
Session: Sciences
Following amputation, zebrafish fins, comprised of intricate skeletal rays and other tissues, perfectly regenerate to their original size and shape regardless of the nature or position of injury. A cell population observed in the regenerating fin, termed “niche”, produces Wnt signals that promote fin outgrowth. As a known transcriptional regulator of the niche, dach plays a role in maintaining proper regeneration. Depending upon the extent of regenerative demand, dach becomes enriched at the distal region of the regenerating fin, and is eventually downregulated once the fin has stopped regenerating. A mechanistic explanation for dach induction, in addition to a thorough understanding of how it regulates the niche, is lacking. To explore the role of dach we used CRISPR/Cas9 gene editing to mutate two isoforms of the dach gene, dachc and dacha. By utilizing high-resolution fin imaging, our data showed that dachc mutants display improper morphology, including: abnormal joint segmentation, fusion of rays, and trident-shaped branching patterns. Surprisingly, this observation was not seen during development, but rather only after amputation and subsequent regeneration. Further, while dacha single mutants exhibited normal regeneration, dachc;dacha double mutants died off at an appreciable rate during development. Our data shows a novel role that dach has in promoting correct branching patterns, in addition to its unique regulation in development versus regeneration. Demonstrating how the misregulation of certain genes like dach can lead to the disruption of growth control mechanisms is critical for understanding the basis of a range of diseases.