Abstract
Photoreceptor disc component (PRCD) is a small protein which is exclusively localized to photoreceptor outer segments, and is involved in the formation of photoreceptor outer segment discs. Mutations in PRCD are associated with retinal degeneration in humans, mice, and dogs. The purpose of this work was to identify PRCD-binding proteins in the retina. PRCD protein-protein interactions were identified when implementing the Ras recruitment system (RRS), a cytoplasmic-based yeast two-hybrid system, on a bovine retina cDNA library. An interaction between PRCD and tubby-like protein 1 (TULP1) was identified. Co-immunoprecipitation in transfected mammalian cells confirmed that PRCD interacts with TULP1, as well as with its homolog, TUB. These interactions were mediated by TULP1 and TUB highly conserved C-terminal tubby domain. PRCD localization was altered in the retinas of TULP1- and TUB-deficient mice. These results show that TULP1 and TUB, which are involved in the vesicular trafficking of several photoreceptor proteins from the inner segment to the outer segment, are also required for PRCD exclusive localization to photoreceptor outer segment discs.
Highlights
Photoreceptors are sensory cells which generate electrical signals in response to light stimuli
Photoreceptor disc component (PRCD) is a protein of crucial importance for normal retinal function
This fact was established over a decade ago, with the identification of PRCD mutations as the cause for retinal degeneration in dogs and humans [9,10]
Summary
Photoreceptors are sensory cells which generate electrical signals in response to light stimuli. These cells are highly compartmentalized, with the nucleus and other cellular organelles located in the inner segment (IS), and the entire machinery for the visual signal transduction cascade (phototransduction) included in the outer segment (OS). Photoreceptor OS are highly modified primary sensory cilia characterized by thousands of stacked disc membranes. The proximal end of the OS is linked to the cell body (i.e., the IS) via a connecting cilium, which is structurally homologous to the transition zone of primary cilia. Unique OS proteins are formed in the IS and transported to the OS across the connecting cilium (reviewed in reference [1]). New discs are formed at the OS base, while old discs are shed from the OS tip [2,3]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
