MicroRNAs in the Mouse Developing Retina

Abstract

The retina is among the highest organized tissues of the central nervous system. To achieve such organization, a finely tuned regulation of developmental processes is required to form the retinal layers that contain the specialized neurons and supporting glial cells to allow precise phototransduction. MicroRNAs are a class of small RNAs with undoubtful roles in fundamental biological processes, including neurodevelopment of the brain and the retina. This review provides a short overview of the most important findings regarding microRNAs in the regulation of retinal development, from the developmental-dependent rearrangement of the microRNA expression program to the key roles of particular microRNAs in the differentiation and maintenance of retinal cell subtypes.

Keywords: Dicer; let-7; miR-124; miR-183/96/182; miR-204/211; miR-9; mouse; retina; transcriptomics.

Figure 1

Schematic summary of the developing mouse retina and main miRNAs involved. (A–D): Schematic showing the various stages of eye development, from optic vesicle formation until the specification of the outer (ONbL) and inner neuroblastic layer (INbL). (E–G): Schematic showing the neural stratification and the sequence of circuit assembly in the mouse retina. E = embryonic day; P = postnatal day. IPL = inner plexiform layer; OPL = outer plexiform layer; RPE = retinal pigment epithelium. G = retinal ganglion cells; A = amacrine cells; H = horizontal cells; B = bipolar cells; P = Photoreceptors; C = cones; R = rods; M = Müller glia. Figure created with BioRender (https://biorender.com/, URL accessed on 20 January 2023).

Figure 2

Summary of the most consistent changing miRNAs in miRNome research (blue, downregulated; red, upregulated) that at least have been retrieved in two of the following studies: [39,41,42,43,46,47,49,51,55,56,58,61,62,63]. The arm (5p or 3p) is indicated when specifically reported.