Purchase this article with an account.
P. Challa, L. J. Camras, I. D. Navarro, C. C. Luna, G. Li, G. K. Klintworth, D. L. Epstein, P. Gonzalez; The Anterior Segment Effects of a Conditional Dicer Knockout in a Rodent Model. Invest. Ophthalmol. Vis. Sci. 2010;51(13):6431.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To evaluate the biological relevance of the regulation of gene expression mediated by microRNAs in the cells of the anterior segment of the eye. MicroRNA function was disrupted by constructing a conditional dicer knockout in living mice.
Targeted deletion of Dicer in the anterior chamber of the eye was accomplished by intracameral injection of 5x106 pfu of an adenoviral vector expressing cre recombinase under the CMV promoter in Dicer1tm1Bdh/J mice, which contain loxP sites on either side of exon 23 of the dicer gene. Control mice were injected in parallel with a recombinant adenovirus expressing EGFP under the same promoter and at the same volume and concentration. Alterations in corneal transparency was monitored by direct inspection via bio-microscopy. Morphological alterations in the cornea and outflow pathway were evaluated by microscopic examination of semi-thin sections 2 months after adenoviral injections.
Loss of microRNA function by deletion of dicer in the anterior chamber resulted in visible corneal opacification in less than 2 weeks after adenoviral injection. Histological examination of the cornea revealed severe morphological changes in Descemet’s membrane, corneal edema, and loss of corneal epithelial cells (Figure 1). Similarly, the trabecular meshwork showed morphological alterations including a noticeable increase in pigment accumulation.
The effects caused by loss of microRNA function through dicer knockdown in the cornea support the concept that regulation of gene expression by microRNAs is important in the maintenance of the normal physiology of adult tissues such as the cornea and the trabecular meshwork.
This PDF is available to Subscribers Only