Abstract
Abstract: :
Purpose: Studies examining the role of local control in the development of myopia implicate a paracrine signalling pathway that runs from the retina, via the choroid, to the sclera, in the regulation of ocular growth. We have used a proteomic approach to identify proteins that are differentially expressed in response to optical defocus (a strong stimulus for myopic development), to identify components of this putative signalling pathway. Methods: Day-old chicks were fitted with a -10D lens over one eye and a plano lens over the fellow eye to control for any possible lens-induced effects, other than optical defocus. To control for possible diurnal effects, all periods of optical defocus were begun and terminated at noon. Ocular tissues were harvested after 7 days of deprived vision and the proteins isolated by sequential extraction. Proteins were separated in the first dimension by narrow-range IEF and then resolved in the second dimension by SDS-PAGE. Gels were silver stained and compared both by eye and software analysis to identify protein spots that were differentially represented between fellow focus-deprived and control eyes. Candidate proteins are being identified by MALDI-TOF mass spectrometry and peptide sequencing. Results: To date, we have identified several protein spots that display altered expression patterns in the retina in response to optical defocus. Other ocular tissues are currently being examined. Conclusion: Proteomic analysis provides a powerful tool to investigate myopia development at a fundamental level.
Keywords: 481 myopia • 397 emmetropization