Transcriptome profiling of ocular surface ectoderm derived from embryonic stem cells, and identification of CACNG6 and AQP3 as its surface markers

AIM: To investigate the transcriptional profiling of ocular surface ectoderm (OSE) derived from human embryonic stem cells (hESC), and identified CACNG6 and AQP3 as the surface markers of OSE. METHODS: hESCs were differentiated into OSE, neuroectoderm (NE), surface ectoderm (SE), and other surface ectoderm (OE) cells in vitro. RNA-seq was performed to analyze transcriptomic profiling of hESC-derived OSE, NE, OE, and SE. The differential expressed genes (DEGs) were identified, and Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, and protein-protein interaction (PPI) network analyses were performed to screen the signals and hub genes associated to OSE commitment. Also, the highly expressed transcription factors (TFs) and membrane proteins (MPs) in OSE cells were identified. RESULTS: Transcriptome analysis revealed that OSE development is dually regulated by signals associated with both SE and NE development. The signaling pathways such as Hippo, encoding extracellular matrix (ECM)-receptor interaction, and transforming growth factor-β (TGF-β) might delineate the surface ectodermal phenotype of OSE, with FN1, COL1A1, and TGFB1 identified as hub genes. Additionally, pathways such as axon guidance, might elucidate the influence of NE in OSE commitment, and with PAX6, LHX2, FOXG1, SOX2, MSI1, and DCLK1 recognized as the hub genes. Genes implicated in retinoic acid (RA) synthesis (ALDH1A1, ALDH1A3, and RDH10) exhibited high expression in OSE, indicating the significant role of the RA signaling pathway in OSE development. Furthermore, OSE-specific transcription factors and surface markers (CACNG6 and AQP3) were identified. CONCLUSION: This study reveals the transcriptome profiling of OSE, which could provide insights into the characteristics of OSE and the underlying molecular mechanisms involved in its derivation.