Purchase this article with an account.
C.S. Ricard; Differential Processing of Myocilin Protein from Human Cells . Invest. Ophthalmol. Vis. Sci. 2003;44(13):3322.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: Mutations in the MYOC gene have been associated with early and late onset primary open angle glaucoma (POAG). The function of myocilin remains unknown. Because my laboratory studies the cellular and molecular mechanisms of POAG, I undertook to analyze the protein chemistry of myocilin secreted by cultured cells from different tissues. Methods: Myocilin obtained from spent medium from normal cultured human cells was used to scale-up protein quantity. Metabolically radiolabeled myocilin was also used for glycoprotein analysis. Myocilin was analyzed by denaturing and non-denaturing gel electrophoresis, isoelectric focusing, carbohydrate analysis, lectin binding, and enzymatic treatments. Results: Myocilin secreted by normal optic nerve head astrocytes was not glycosylated, whereas brain and immortalized cells secreted N- or O-glycosylated myocilin or both. The carbohydrates were analyzed by lectins and glycolytic enzymes. Conclusions: My results demonstrate that myocilin is not processed the same way in different cell types. The function is unknown for this protein, but glycosylation differences would affect extracellular interactions, hydration and space between cells and ECM.
This PDF is available to Subscribers Only