Development of an undergraduate cell biology laboratory to assess pigmentation and cell size in a zebrafish model of uveal melanoma

This study outlines a two-week laboratory module for an authentic cell biology undergraduate research experience that uses zebrafish (Danio rerio), a popular model organism for research. Previous research has indicated that course-based undergraduate research experiences such as this one increase student confidence, active learning, and retention. During this research experience, students investigate variations in pigmentation in the caudal fins of wild type and transgenic fish (Tg(mitfa:GNAQQ209L)). The transgenic fish express a hyperactive G protein, GNAQQ209L, under the melanocyte-specific mitfa promoter, offering insights into uveal melanoma, a common eye cancer. Students specifically analyze the black pigmented cells, melanophores, within the caudal fin. We determined that the transgenic zebrafish have increased pigmentation in their caudal fins but smaller melanophores. These results suggest there are more melanophores in the Tg(mitfa:GNAQQ209L) fish compared to the wild type. Future undergraduate research could investigate these cellular differences. This research experience imparts microscopy and image analysis skills and instills the ability to grapple with large datasets, statistical tests, and data interpretation in alignment with biology education principles. Post-lab surveys reveal students attain confidence in the above skills and in handling animals, along with a deeper appreciation for model organism research and its relevance to cancer cell biology.