ABSTRACT
Retinal ganglion cells (RGCs) are the projection neurons of the retina, and their death promotes an irreversible blindness. Several factors were described to control their genesis during retinal development. These include Atoh7, a major orchestrator of the RGC program, and downstream targets of this transcription factor, including Pou4f factors, that in turn regulate key aspects of terminal differentiation. The absence of POU4F family genes results in defects in RGC differentiation, aberrant axonal elaboration and, ultimately, RGC death. This confirms the requirement of POU4F factors for RGC development and survival, with a crucial role in regulating RGC axon outgrowth and pathfinding. Here, we have investigated in vivo whether ectopic Pou4f2 expression in late retinal progenitor cells (late RPCs) is sufficient to induce the generation of cells with RGC properties, including long-range axon projections. We show that Pou4f2 overexpression generates RGC-like cells that share morphological and transcriptional features with RGCs that are normally generated during early development and extend axonal projections up to the brain. In conclusion, these results show that POU4F2 alone is sufficient to promote the crucial properties of projection neurons that arise from retinal progenitors outside their developmental window.
Footnotes
Author contributions
Conceptualization: M.R.-M., M.S.S.; Data curation: V.M.O.-V., J.M.R., V.M.F.-C., A.B., M.L.V., M.S.S.; Formal analysis: V.M.O.-V., J.M.R., R.L., A.B., M.L.V., M.S.S.; Funding acquisition: R.L., R.A.P.M., A.B., M.L.V., M.S.S.; Investigation: V.M.O.-V., J.M.R., V.M.F.-C., C.H.C., B.C.d.T., P.L.S.-F., A.B., M.S.S.; Methodology: V.M.O.-V., J.M.R., V.M.F.-C., C.H.C., B.C.d.T., P.L.S.-F., M.R.-M.; Resources: M.L.V., M.S.S.; Supervision: R.A.P.M., A.B., M.L.V., M.S.S.; Validation: V.M.O.-V.; Visualization: M.S.S.; Writing – original draft: V.M.O.-V., M.S.S.; Writing – review & editing: V.M.O.-V., J.M.R., R.L., R.A.P.M., M.R.-M., A.B., M.L.V., M.S.S.
Funding
This work was supported by the International Retinal Research Foundation (IRRF) (M.S.S. and A.B.), the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) (160968/2018-6 and 200913/2022-0 to V.M.O.-V.; 402078/2022-5 to M.S.S., M.L.V. and A.B.), the Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) (E-26/200.214/2020 to V.M.O.-V., and E-26/211.301/2021 to R.L and M.S.S.) and the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) (88887.512251/2020-00 to V.M.O-V.).
Data availability
Raw and processed scRNA-seq data generated in this study have been deposited in GEO under accession number GSE269337.
