Abstract
Purpose:
Protein phosphorylation plays an important role in regulating a wide range of cellular activities. However, its role in the mechanism of eye growth has not been characterized. The purpose of this study is to profile the phosphoproteins in lens induced ametropia in chicks.
Methods:
White leghorn chicks (4-day old) worn either -10 or +10D lenses for 3 days to induce myopia and hyperopia respectively. Refraction and ocular biometry were measured before and after lens wear. After the lens treatment, the retina tissues were removed. It was further homogenized, extracted and double digested with trypsin and GluC. The retinal peptides were enriched with titanium dioxide and then injected to a 1D nano-flow liquid chromatography tandem mass spectrometry. Protein identifications are performed with ProteinPilot software in IPI chick database.
Results:
Expectedly, the chick eyes developed significant and expected ametropia according to refraction and A-scan results after three days of lens treatment. A total of 718 peptides in lens-induced myopic/hyperopic retina were detected with phosphorylation. The specific site of phosphorylation of each peptide was identified. These phosphopeptides can be further divided into three groups: common peptides in myopia and hyperopia (218 pairs); peptides that appear only in myopia (129 peptides); peptides that appear only in hyperopia (163 peptides).
Conclusions:
The study demonstrated the feasibility of phosphoproteomic analysis in ametropic chick retina in a high-throughput manner. Together with quantitative proteomic approaches, it may provide the next level of understanding of the protein changes that drive the differential eye growth process.
Keywords: 605 myopia •
663 proteomics •
688 retina