Kevin Cruz-Colón is a graduate student in the Neuroscience Graduate Program. He completed his undergraduate degree in Biological Sciences from the University of Puerto Rico, Ponce. He is working on a project to understand the molecular processes regulating the membrane protein composition of the light-sensitive outer segment organelle in photoreceptor cells.

Amanda Travis, PhD was award a postdoctoral fellowship from the Vision Research Training Program at the University of Michigan. Human mutations in the small GTPase, Arl3, cause a variety of inherited retinal dystrophies, including rod-cone dystrophy and retinitis pigmentosa. These mutations are generally believed to destabilize Arl3 or impair its interactions with binding partners; however, precise pathobiological outcomes has yet to be studied in vivo.  Amanda uses in vivo mouse models as well as in vitro biochemistry and cell-based experiments to understand the cellular consequences dominant Arl3 mutations
have in rod photoreceptors. Congratulations Amanda! 

In our recent manuscript, ”The GARP Domain of the Rod CNG Channel’s β1-subunit Contains Distinct Sites for Outer Segment Targeting and Connecting to the Photoreceptor Disc Rim” published in the Journal of Neuroscience we found that outer segment delivery of the CNG channel utilizes the conventional secretory pathway, requires pre-assembly of its α1 and β1 subunits, and CNG channel sorting into the plasma membrane of the outer segment occurs independently of its initial targeting, which we showed is encoded by a glutamic acid-rich region on the N-terminus of CNGβ1. We also identified a proline-rich region of CNGβ1, adjacent to its targeting region, that connects the CNG channel to photoreceptor disc rims, likely through an interaction with peripherin-2. These findings reveal fine functional specializations within the structural domains of the CNG channel and help expand our understanding of how neurons populate their critical functional compartments.