Micro RNAs (miRNAs) are noncoding, single-stranded RNA molecules about 21-33 nucleotides in length (Curr Biol 2002; 12:735-739.2.; Nature 2004; 431:350-355). In some species, a mature miRNA is complementary to the 3′ untranslated region (UTR) of one or more messenger RNAs (mRNAs). The annealing of a micro RNA to its target messenger RNA causes an inhibition of protein translation, and/or cleavage of the messenger RNA. Micro RNAs are capable of regulating cell growth, differentiation, and apoptosis (Nature 2004; 431:350-355; Proceedings of the National Academy of Sciences of the United States of America 2006; 103:7024-7029; British journal of cancer 2006; 94:776-780; Science 2005; 310:1817-1821). Therefore, dysregulation of miRNAs may lead to human diseases. In this respect, several exciting researches have been focused on the role of miRNAs in cancers.
The PAX6 gene belongs to a highly conserved family of transcription factors containing the paired and homeobox DNA-binding domains. PAX6 gene is involved in the development of the central nervous system and eye development. It plays a significant role during the induction of the lens and retina differentiation, and has been considered the master gene for eye development (Exp Eye Res 2006; 83:233-234; Brain Res Bull 2008; 75:335-339). The inventors previously reported the 3′ untranslated region single nucleotide polymorphism (SNP) rs662702 of the PAX6 gene is associated with extreme myopia (Invest Ophthalmol Vis Sci 2011; 52:35000-35005). In the subsequent report, the inventors proved that the preceding single nucleotide polymorphism is located in the microRNA-328 (miR-328) binding site on the PAX6 gene (Invest Ophthalmol Vis Sci. 2012 May 31; 53(6):2732-9). The functional assay suggested that the C allele of the single nucleotide polymorphism can reduce PAX6 protein levels and that significantly increases risk of myopia.
Signals which originate from the retina can be conveyed to the sclera (Vis Neurosci 2005; 22:251-261), especially those from the photoreceptors and the retinal pigment epithelium (RPE). Therefore, investigating the interaction between retinal pigment epithelium cells and scleral cells may provide more insight to the development of myopia.
However, in the past, there have been no reports about the role of micro RNA on the development of myopia, and at present, there are no reports of research related to using RNA interference as a medicament for treating and/or preventing myopia.