Abstract
Purpose:
To identify the protein profiles of mouse retina and vitreous and determine unique protein pathways and interaction networks in these tissues.
Methods:
Vitreous and retina samples from normal mice were collected by an evisceration technique developed in our laboratory and pooled. Samples were analyzed in technical triplicate by LC-MS/MS. The proteins discovered were further analyzed using bioinformatic software to determine significant pathways present, statistically significant protein expression differences between vitreous and retina, gene ontologies, and protein interaction networks.
Results:
In the retina, we identified 5,729 unique spectra with 106,734 peptide hits, corresponding to 1,682 unique proteins and 1,085 unique spectra with 45,507 peptide hits, corresponding to 677 unique proteins in the vitreous. Unbiased clustering of the proteins verified that the vitreous and retina were significantly different with different gene ontology distributions. The most highly represented pathways that distinguished the retina from the vitreous (p < 0.05) were neuronal cell synapses (LRRK2), pyruvate metabolism, neurophysiological processes, apoptosis/survival, cytoskeletal remodeling, and G-protein signaling (CFTR). Pathways that distinguished the vitreous from the retina (p < 0.05) were phenylalanine metabolism and nitrogen metabolism. Some clusters of interacting proteins were identified in both the retina and vitreous. These included crystallin cell regulation and oxidative stress proteins.
Conclusions:
We identified several unique proteins, pathways, and interaction networks that distinguish the normal mouse retina and vitreous. This methodology can be applied to mouse models of human vitreoretinal disease.
Keywords: 663 proteomics •
763 vitreous •
688 retina