Expression of Wild Type and Truncated Myocilins in Trabecular Meshwork Cells: their Subcellular Localization.
- Author:
Won Hee HUR
1
;
Chang Won KEE
Author Information
1. Department of Ophthalmology, Samsung Medical Center Sungkyunkwan University, College of Medicine, Korea. cwkee@smc.samsung.co.kr
- Publication Type:Original Article
- Keywords:
Adenoviral vector;
Myocilin;
Subcellular localization;
Trabecular meshwork cell
- MeSH:
Antibodies;
Blotting, Western;
Humans;
Matrix Metalloproteinase 3;
Microtubules;
Mitochondria;
Organelles;
Trabecular Meshwork*
- From:Journal of the Korean Ophthalmological Society
2003;44(4):955-964
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: To investigate subcellular localizations of wild type myocilin and trunctated (Q368X) myocilin in cultured human trabecular meshwork (TM) cells. METHODS: GFP and GFP tagged truncated myocilin, full-length myocilin, and stromelysin were expressed in TM cells using adenoviral vectors, and their secretory properties were examined by western blotting. To determine the subcellular localizations of myocilins, cellular organelles of the infected TM cells were stained with antibodies or orgenelle specific fluorescent indicators and examined under confocal microscope. RESULTS: Wild type myocilin was expressed as discrete fine vesicles in the perinuclear region of TM cells as well as in ER, but not in microtubules or mitochondria. Colocalization of wild type and truncated myocilin, indicative of in vivo interaction of the proteins, was also observed in cells co-expressing the proteins. Truncated myocilin was found to be accumulated as aggregates in ER, and inhibited the secretion of normal myocilin. CONCLUSIONS: Our result suggests that intracellular accumulation of truncated myocilin may cause a dysfunction of the cells, resulting in alterations in structural compartmentalization of trabecular ECM and obstruction of aqueous outflow.
