Purchase this article with an account.
Igor V Peshenko, Elena V Olshevskaya, Alexander M Dizhoor; Identification of possible target binding site in retinal degeneration 3 (RD3) protein. Invest. Ophthalmol. Vis. Sci. 2016;57(12):3173.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Regulation of retinal membrane guanylyl cyclase, RetGC1, plays important role in rod and cone physiology. Retinal degeneration 3 (RD3) protein associates with RetGC, inhibits catalytic activity of the enzyme and prevents the cyclase activation by GCAPs [1,2]. RD3 is also crucial for the proper expression of both RetGC isozymes in photoreceptors . The purpose of this study was to identify the target -binding site in RD3 molecule.
Non-tagged or GFP-tagged human RD3 was expressed in E. coli or in HEK293 cells, and the recombinant RD3 was then tested in RetGC activity assay in vitro or probed for co-localization with RetGC1 in HEK293 cells using the in cyto methodology previously described in detail .
We probed the primary amino acid sequence of a human RD3 by introducing 3 to 6 amino acid residues long amino acid substitutions in those regions of the RD3 primary structure that were most conserved among different mammalian species. The GFP-tagged RD3 mutants were co-expressed with mOrange-tagged RetGC1 in living HEK293 cells to evaluate the effect of the substitutions on the ability of RD3 to bind and co-localize with RetGC1 in the membranes. The mutants that showed impaired binding to membrane cyclase in HEK293 cells also failed to properly suppress activation of RetGC1 by GCAP1 in vitro. We have identified two regions in the RD3 primary structure where the amino acid substitutions produced the most prominent effect.
We identified the putative cyclase–binding interface portion of the RD3 primary structure that can directly interact with its target enzyme, RetGC1. References:  Azadi et al. (2010) Proc. Natl. Acad. Sci. USA 107, 21158-63;  Peshenko et al. (2011) Biochemistry 50, 9511-19;  Zulliger et al. (2015) J. Biol. Chem. 290, 3488-99;  Peshenko et al. (2015) J. Biol. Chem. 290, 19584-96
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.
This PDF is available to Subscribers Only