HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (6) Citing Articles via Google Scholar Google Scholar Articles by Obazawa, M. Articles by Iwata, T. Search for Related Content PubMed PubMed Citation Articles by Obazawa, M. Articles by Iwata, T.

Analysis of Porcine Optineurin and Myocilin Expression in Trabecular Meshwork Cells and Astrocytes from Optic Nerve Head

¹From the National Institute of Sensory Organs, National Tokyo Medical Center, Tokyo, Japan; the ²Departments of Ophthalmology and ⁴Molecular Biology, Keio University School of Medicine, Tokyo, Japan; and the ³Department of Nursing, School of Health Science, Tokai University, Isehara, Kanagawa, Japan.

PURPOSE. To determine the cDNA sequences and analyze the expression of porcine optineurin and myocilin in trabecular meshwork cells (TMCs) and astrocytes from the optic nerve head under normal and experimental conditions.

METHODS. Both porcine optineurin and myocilin were cloned to determine the cDNA sequences. Porcine TMCs and astrocytes were isolated and treated with dexamethasone (500 nM) for 2 weeks, incubated under hypoxic conditions (7% O₂) for 72 hours, or exposed to 33 mm Hg hydrostatic pressure for 72 hours. A 10% mechanical stretch for 24 hours was also performed on TMCs. The expression level of the optineurin and myocilin transcripts was analyzed by real-time quantitative PCR.

RESULTS. The sequences of porcine optineurin and myocilin cDNA were determined, and the expression of both genes was confirmed in both TMCs and astrocytes. Amino acid sequences of porcine optineurin and myocilin were homologous to those of humans by 84% and 82%, respectively, and shared protein motifs and modification sites. The expression of myocilin mRNA by TMCs and astrocytes was increased by 8.0- and 5.5-fold, respectively, after exposure to dexamethasone. In contrast, the expression of optineurin was suppressed to 68% in TMCs and 48% in astrocytes after exposure to dexamethasone. A significant reduction of myocilin expression was observed after 72 hours of incubation under hypoxic conditions in both types of cells, whereas optineurin was not affected. Hydrostatic pressure for 72 hours and mechanical stretching for 24 hours had minimal affects on gene expression of both optineurin and myocilin.

CONCLUSIONS. The high homology of porcine optineurin and myocilin to the comparable human genes indicates that pigs can be used to study changes in gene expression in hypertensive eyes. The alterations in expression of myocilin but not of optineurin under stress suggest that different mechanisms in the phenotype of glaucoma associated with the two genes are involved in development of glaucoma.

This article has been cited by other articles:

				R. M. Sappington and D. J. Calkins Pressure-Induced Regulation of IL-6 in Retinal Glial Cells: Involvement of the Ubiquitin/Proteasome Pathway and NF{kappa}B. Invest. Ophthalmol. Vis. Sci., September 1, 2006; 47(9): 3860 - 3869. [Abstract] [Full Text] [PDF]

				R. M. Sappington, M. Chan, and D. J. Calkins Interleukin-6 protects retinal ganglion cells from pressure-induced death. Invest. Ophthalmol. Vis. Sci., July 1, 2006; 47(7): 2932 - 2942. [Abstract] [Full Text] [PDF]