Ocular Genetics Unit, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia.
Vision Sciences, School of Psychology, Faculty of Science and Hunter Medical Research Institute, University of Newcastle, Callaghan, New South Wales, Australia.
Invest Ophthalmol Vis Sci. 2018 Mar 1;59(3):1425-1434. doi: 10.1167/iovs.16-21278.
Posterior scleral remodeling accompanies myopia. In guinea pigs developing myopia, the region around the optic nerve (peripapillary zone, PPZ) rapidly expands followed by inhibition in eye size in the periphery. We studied the differential gene expression in the sclera that accompanies these changes.
Guinea pigs were form-deprived (FD) for 2 weeks to induce myopia, while the fellow eye served as a control. After 2 weeks, the PPZ and the peripheral temporal sclera were isolated in representative animals to extract the RNA. RNA sequencing was undertaken using an Illumina HiSeq 2000, with differential expression analyzed using Voom and pathways analyzed using the Ingenuity Pathway Analysis tool. RNA from additional PPZ and peripheral temporal sclera in FD and fellow eyes was used for validation of gene expression using quantitative real-time PCR (qRT-PCR).
In myopic sclera, 348 genes were differentially expressed between PPZ and the peripheral temporal region (corrected P < 0.05), of which 61 were differentially expressed in the PPZ between myopic and control eyes. Pathway analyses of these gene sets showed the involvement of Gαi signaling along with previously reported gamma-aminobutyric acid (GABA) and glutamate receptors among numerous novel pathways. The expression pattern of three novel genes and two myopia-related genes was validated using qRT-PCR.
Gene expression changes are associated with the rapid elongation that occurs around the optic nerve region during the development of myopia. A prominent change in Gαi signaling, which affects cAMP synthesis and thus collagen levels, may be critical in mediating the regional changes in myopic sclera.
后巩膜重塑伴随着近视的发生。在发生近视的豚鼠中，视神经周围区域（视盘周围区域，PPZ）迅速扩张，随后周边眼轴停止生长。我们研究了伴随这些变化的巩膜的差异基因表达。
用形觉剥夺（FD）法使豚鼠近视 2 周，同时作为对照的对侧眼不进行 FD。2 周后，在代表性动物中分离 PPZ 和周边颞侧巩膜以提取 RNA。使用 Illumina HiSeq 2000 进行 RNA 测序，使用 Voom 分析差异表达，并使用 Ingenuity Pathway Analysis 工具分析途径。使用 FD 和对照眼的额外 PPZ 和周边颞侧巩膜的 RNA 进行定量实时 PCR（qRT-PCR）验证基因表达。
在近视巩膜中，PPZ 和周边颞侧区域之间有 348 个基因差异表达（校正 P < 0.05），其中 61 个基因在近视眼中的 PPZ 与对照眼中差异表达。这些基因集的途径分析显示 Gαi 信号的参与，以及之前报道的γ-氨基丁酸（GABA）和谷氨酸受体以及许多新途径。使用 qRT-PCR 验证了三个新基因和两个近视相关基因的表达模式。
基因表达变化与近视发展过程中视神经区域的快速伸长有关。Gαi 信号的显著变化可能对 cAMP 合成有影响，从而影响胶原水平，这可能是介导近视巩膜区域变化的关键因素。
