Dataset Information

Network biology analysis of P23H rhodopsin interactome identifies protein and mRNA quality control mechanisms

ABSTRACT: Rhodopsin is essential for phototransduction, and many rhodopsin mutations cause heritable retinal degenerations. The P23H rhodopsin variant generates a misfolded rhodopsin protein that photoreceptors quickly target for degradation by mechanisms that are incompletely understood. To gain insight into how P23H rhodopsin is removed from rods, we used mass spectrometry to identify protein interaction partners of P23H rhodopsin immunopurified from RhoP23H/P23H mice and to compare with protein interaction partners of wild-type rhodopsin from Rho+/+ mice. We identified 286 proteins associated with P23H rhodopsin and 276 proteins associated with wild-type rhodopsin. Only 113 proteins were shared between wild-type and mutant rhodopsin protein interactomes. In the P23H rhodopsin protein interactome, we saw loss of phototransduction, retinal cycle, and rhodopsin protein trafficking proteins but gain of ubiquitin-related proteins when compared with the wild-type rhodopsin protein interactome. In the P23H rhodopsin protein interactome, we saw significant enrichment of gene ontology terms related to ER-associated protein degradation, ER stress, and translation. Protein-protein interaction network analysis revealed that translational and ribosomal quality control proteins were the most significant regulators in the P23H rhodopsin protein interactome. The protein partners identified in our study may provide new insights into how photoreceptors recognize and clear mutant rhodopsin and may offer novel targets involved in retinal degeneration pathogenesis.

INSTRUMENT(S): LTQ Orbitrap

ORGANISM(S): Mus Musculus (ncbitaxon:10090)

SUBMITTER: Jonathan H. Lin