Abstract
Purpose:
The study aim was to determine microRNA (miRNA) expression profiles of ocular tissues in form-deprivation induced myopic mice.
Methods:
Fifteen C57BL/6J mice (Jackson Laboratory, Bar Harbor, ME) were used in this study. Form-deprivation myopia was induced in postnatal day 24 (P24) C57BL/6J mice by applying a frosted hemispherical plastic diffuser over the right eye for 10 days. Total RNA was isolated from the whole eye, retina, and sclera and used for miRNA expression profiling with the Agilent mouse miRNA microarray(Agilent Technologies, Inc., Santa Clara, CA). The microarray raw data were processed by subtracting background noise and performing log2 transformation. Sample outliers were removed. The normalized microarray data were analyzed using ANOVA to identify differences in miRNA expression level between myopic and contralateral control eyes.
Results:
ANOVA revealed 75 miRNAs with differential expressions [fold change (FC) >= 1.5] from the whole eye, retina, and sclera. Multiple members of the miRNA family -302 (b and c), -466 (c, g, h, and j), and -669 (a, b, e, and o), and three members of the 290-295 cluster (290, 291 and 294) showed increased or decreased differential expressions. Member examples included mmu-miR-302c [FC= 3.2; p=2.1E-2], mmu-miR-466c [FC=2.3; p=2.0E-3], mmu-miR-466j [FC=3.1; p=8.5E-4], and mmu-miR-669b [FC=2.1; p=9.0E-4] from the whole eye; mmu-miR-294 [FC=1.5; p= 2.4E-2] and [FC=2.3; p=8.0E-5] from retina and sclera separately. MiR-302 and the 290-295 member cluster are involved in cell pluripotency maintenance. Other differentially expressed miRNA examples included mmu-miR-15a [FC=2.2; p=1.1E-3] and mmu-miR-16-1[FC=2.1; p=4.6E-4] from the whole eye, and mmu-miR-21[FC=2.2; p=1.7E-3] from retina. MiR-15, 16, and 21 are involved in growth and development regulation.
Conclusions:
Differential expression of miRNAs in several ocular tissues upon induction of experimental myopia in mice suggests a developmental and regulatory role in eye growth, and can potentially serve as therapeutic targets for treating myopia.
Keywords: 605 myopia •
708 sclera •
535 gene microarray