Temporal and Spatial Expression Patterns of TRPM1 and PKCα During Retinal Development in the Little Skate (Leucoraja erinacea)
Elvira Magaña
Department of Biology
Faculty Supervisor: Ivan A. Anastassov
The Little Skate (L. erinacea) is an ideal model for studying retinal development in simplex retinas, as visual processing relies exclusively on rod photoreceptors. This study investigates the expression patterns of transient receptor potential cation channel subfamily M member 1 (TRPM1) and protein kinase C-alpha (PKCα) during retinal development. In duplex retinas, TRPM1 is expressed in all ON-bipolar cells, including rod bipolar cells (RBCs), while PKCα marks RBCs specifically. We track the expression of both molecules using multiplex in-situ and histology approaches. If TRPM1 and PKCα are expressed at different times and in different cells, it may indicate distinct bipolar cell populations are present in skate, each following their own developmental programs. Alternatively, these markers may appear at different times within the same cell type, indicating less bipolar cell diversity. For example, in mouse RBCs, mGluR6 reaches dendritic tips before TRPM1, suggesting timing differences play a role in retinal wiring. Furthermore, identifying TRPM1+/PKCα- cells would reveal non-rod bipolar cells in the skate retina, revealing for the first time bipolar cell diversity in any simplex retina. These findings are important for our understanding of cell differentiation and retinal wiring in species with unusual visual systems.