MicroRNAs of the mammalian eye display distinct and overlappingtissue specificity

[摘要] Purpose: In mammals, endogenous, noncoding RNAs, designated asmicroRNAs (miRNAs), inhibit the translation of a target messenger RNA,thereby silencing protein production. MiRNAs have been shown to regulatemany aspects of development and differentiation in a wide range oftissues. Surprisingly, little consideration has been directed towardscharacterizing the expression of miRNAs in mammalian ocular tissues.Methods: Low molecular weight (LMW) RNA isolated from the adultmouse corneal epithelium, lens/ciliary body, and a retina fractions ofthe eye was analyzed by miRNA arrays. The validity of the miRNAexpression profiles were confirmed by northern blots and the tissuedistribution of selected miRNAs was determined by in situhybridization.Results: MiRNAs exhibited distinct tissue and cell-type specificityin the ocular regions studied. MiRNA (mir)-184 had the highesthybridization signal in the corneal and lens arrays. In situhybridization analysis revealed that mir-184 was expressed in the basaland immediately suprabasal cells of the corneal epithelium. In contrast,expression of mir-205 was detected throughout the anterior segmentalepithelia as well as in the epidermis. Within the lens, expression ofmir-184 was more strongly expressed in the epithelial cells of thegerminative zone, whereas expression of mir-204 was uniformly expressedin all lens epithelial cells. Mir-181, -182, and -183 were detected inretinal and brain tissues, and their distribution patterns within theretina were both distinct and overlapping.Conclusions: The tissue and cell specificity of ocular miRNAssuggests that these noncoding RNAs may be regulating aspects ofdevelopment and differentiation.

[学科分类] 生物化学/生物物理