Project description:Otx2 has been shown to be non cell autonomously required for photoreceptor cell survival in the adult mouse RPE. This study aims to identify Otx2 DNA binding profile in both RPE and neural retina to i) identify direct targets of Otx2 in the RPE ii) compare Otx2 binding profile in neural retina and RPE to unveil hidden functions in the neural retina. WT and GFP antibodies were used to perform two independent ChIP-seq experiments using Illumina GAIIx.
Project description:Otx2 has been shown to be non cell autonomously required for photoreceptor cell survival in the adult mouse RPE. This study aims to identify Otx2 DNA binding profile in both RPE and neural retina to i) identify direct targets of Otx2 in the RPE ii) compare Otx2 binding profile in neural retina and RPE to unveil hidden functions in the neural retina.
Project description:Tissue-specific transcription factors control the transcriptome through an association with noncoding regulatory regions (cistromes). Identifying the combination of transcription factors that dictate specific cell fate, their specific cistromes and examining their involvement in complex human traits remain a major challenge. Here we focus on the retinal pigmented epithelium (RPE), an essential lineage for retinal development and function and the primary tissue affected in age-related macular degeneration (AMD), a leading cause of blindness. By combining mechanistic findings in stem-cell-derived human RPE, in- vivo functional studies in mice and global transcriptomic and proteomic analyses, we revealed that the key developmental transcription factors LHX2 and OTX2 function together in transcriptional module containing LDB1 and SWI/SNF (BAF) to regulate the RPE transcriptome. Importantly, the intersection between the identified LHX2-OTX2 cistrome with published expression quantitative trait loci, ATAC-seq data from human RPE, and AMD GWAS data, followed by functional validation using a reporter assay, revealed a causal genetic variant that affects AMD risk by altering TRPM1 expression in the RPE through modulation of LHX2 transcriptional activity on its promoter. Taken together, the reported cistrome of LHX2 and OTX2, the identified downstream genes and interacting co-factors reveal the RPE transcription module and uncover a causal regulatory risk SNP in the multifactorial common blinding disease AMD.
Project description:The Otx2 homeobox transcription factor is essential for gastrulation and early neural development. We generated Otx2 conditional knockout (cKO) mice to investigate its roles in telencephalon development after E9.0. We conducted transcriptional profiling and in situ hybridization to identify genes de-regulated in Otx2 cKO ventral forebrain. In parallel, we used ChIP-seq to identify enhancer elements, OTX2 binding motif, and which de-regulated genes are likely direct targets of Otx2 transcriptional regulation. We found that Otx2 was essential in septum specification; regulation of Fgf signaling in the rostral telencephalon; and medial ganglionic eminence (MGE) patterning, neurogenesis, and oligodendrogenesis. Within the MGE, Otx2 was required for ventral but not dorsal identity; this is the first demonstration of a transcription factor that contributes to regional patterning within the MGE. Microdissected subpallium (septum, MGE, and LGE ) from wildtype E12.5 CD-1 embryos was used in three independentanti-OTX2 ChIP-seq experiments.