As a graduate student in the Yelick Lab at Tufts University's Graduate School for Biomedical Sciences, I was a key player in the lab's work using zebrafish to model and study diseases of cartilage and bone development.
I led a team of undergraduates and technicians in our work on two main projects:
Creating the first adult zebrafish model of human FOP
For my main graduate project, I was interested in determining whether zebrafish could serve as a good animal model for the rare human disease, Fibrodysplasia Ossificans Progressiva (FOP). The lab knew from previous work that zebrafish harboring loss of function mutations in FOP-associated gene, Acvr1l, do not survive larval development. Because of this, we developed zebrafish carrying a heat shock-inducible copy of mutant Acvr1l to bypass the larval lethality. I established an automated heat shock system that allowed me to heat shock adult zebrafish for months at a time. These heat shocked animals were the first adult zebrafish model of FOP. We were able to show that these animals develop many FOP-like phenotypes, such as spinal lordosis, vertebral fusions, and heterotopic ossification (LaBonty et al, 2017). Interestingly, when injured, the FOP-like zebrafish do not develop additional heterotopic bone, which is in contrast to the injury response in human patients and FOP mouse models (LaBonty et al, 2018).
Identifying mechanisms driving zebrafish cartilage and bone loss
In the early days of the Yelick lab, a large scale mutagenesis screen was completed to identify genes regulating zebrafish tooth and bone formation (Connolly and Yelick, 2010; Andreeva et al, 2011). The lab isolated numerous zebrafish lines carrying heterozygous or homozygous mutations, some which resulted in larval lethality, but most which survived and showed mineralization defects into adulthood. During my rotation in the lab, I assisted in the characterization of one of these lines, carrying a mutation in the gene wdr43 that introduces a premature stop codon. We showed that Wdr43 is involved in ribosome biogenesis and that this role is important for the proper development of neuroepithelial tissues and neural crest cell-derived tissues, such as pharyngeal arch cartilage (Zhao et al, 2014).
I also spent many summers mentoring students on mini-projects working with other lines isolated from the mutagenesis screen. Students completed DNA extractions from mutant and wild type siblings for next generation sequencing analysis and using techniques such as whole mount Alizarin Red staining to visualize mineralized tissue defects in each line. As we had so many different lines to work with, it was easy for each student to have ownership of their independent project and to study whatever they found most interesting. These images show just a few of the lines that students studied during their time in the lab.