Quantifying sex-specific differences during zebrafish fin regeneration - Summary The zebrafish regenerating fin is an important model system to understand mechanisms underlying regeneration, skeletal development, and skeletal disease. Although overt phenotypic sex-differences during fin regeneration have not been observed, not all sexually dimorphic traits are evident. Thus, the possibility that there are measurable sex-differences cannot be ruled out. Indeed, one rationale for the 2016 NIH policy to consider sex as a biological variable (SABV) was that important biological information could be missing from studies that relied on a single sex, or that ignored sex when reporting cell/animal data. Importantly, while the inclusion of both sexes is appropriate under the SABV policy, this may not be sufficient over the long-term to reveal the complete biology underlying regeneration. Therefore, the long-term goal of this project is to improve the consideration of SABV for research involving fin regeneration. The overall objectives for this proposal are to collect, analyze, and report, phenotypic and transcriptomic data by sex during fin regeneration. The central hypothesis is that while the majority of experimental studies during zebrafish regeneration includes both sexes, without collecting/analyzing data separately, relevant sex-dependent differences may be lost. The rationale is that completion of this project will reveal both sex-dependent and sex-independent outcomes. In turn, these data will better inform future research by identifying specific characteristics of fin regeneration better served by collecting/analyzing/reporting data by sex. The overall objectives will be achieved using two specific aims. The goal of Aim 1 is to reveal sex-dependent phenotypes during fin regeneration. Fins at different stages of regeneration will be analyzed for differences in commonly measured parameters including total regenerate length, fin ray regenerate length, segment length, and cell proliferation. The goal of Aim 2 is to reveal sex- dependent differential gene expression during fin regeneration. Fins at different stages of regeneration will be analyzed to identify all differentially expressed genes. This proposal is innovative because completion will generate resources that will facilitate the improved application of SABV during fin regeneration research. This proposal is significant because these resources will drive better informed decisions about collecting/analyzing/reporting data based on sex, and will therefore positively impact future experimental design.
