Project description:In development, embryonic ectoderm differentiates into several lineages including neuroectoderm and surface ectoderm, through the mechanism largely unclear. Here we report that OVOL2 is required for the transcriptional program of corneal epithelium cell(CEC)s, a derivative of surface ectoderm, and it might regulates the differential transcriptional programs between the two lineages. By a functional screening, we identified transcription factors (TFs) maintaining human CECs. OVOL2 was necessary to maintain the transcriptional program in CECs, particularly through repressing expression of mesenchymal genes. OVOL2 combined with several TFs were able to activate the transcriptional program of CECs in fibroblasts, accompanied by induction of chromatin landscape. Moreover, our analysis revealed that neuroectoderm derivatives express some of mesenchymal genes. In fact, OVOL2 alone was able to induce the transcriptional program of CECs in neural progenitor cells (NPCs) through repression of mesenchymal genes as well as activation of epithelial genes. Our data suggest that the difference between the transcriptional programs of surface ectoderm-derivatives and neuroectoderm-derivatives is regulated in part by the reciprocally-repressive mechanism between epithelial and mesenchymal genes that is seen in epithelial-to-mesenchymal transition.
Project description:In development, embryonic ectoderm differentiates into several lineages including neuroectoderm and surface ectoderm, through the mechanism largely unclear. Here we report that OVOL2 is required for the transcriptional program of corneal epithelium cell(CEC)s, a derivative of surface ectoderm, and it might regulates the differential transcriptional programs between the two lineages. By a functional screening, we identified transcription factors (TFs) maintaining human CECs. OVOL2 was necessary to maintain the transcriptional program in CECs, particularly through repressing expression of mesenchymal genes. OVOL2 combined with several TFs were able to activate the transcriptional program of CECs in fibroblasts, accompanied by induction of chromatin landscape. Moreover, our analysis revealed that neuroectoderm derivatives express some of mesenchymal genes. In fact, OVOL2 alone was able to induce the transcriptional program of CECs in neural progenitor cells (NPCs) through repression of mesenchymal genes as well as activation of epithelial genes. Our data suggest that the difference between the transcriptional programs of surface ectoderm-derivatives and neuroectoderm-derivatives is regulated in part by the reciprocally-repressive mechanism between epithelial and mesenchymal genes that is seen in epithelial-to-mesenchymal transition.
Project description:In development, embryonic ectoderm differentiates into several lineages including neuroectoderm and surface ectoderm, through the mechanism largely unclear. Here we report that OVOL2 is required for the transcriptional program of corneal epithelium cell(CEC)s, a derivative of surface ectoderm, and it might regulates the differential transcriptional programs between the two lineages. By a functional screening, we identified transcription factors (TFs) maintaining human CECs. OVOL2 was necessary to maintain the transcriptional program in CECs, particularly through repressing expression of mesenchymal genes. OVOL2 combined with several TFs were able to activate the transcriptional program of CECs in fibroblasts, accompanied by induction of chromatin landscape. Moreover, our analysis revealed that neuroectoderm derivatives express some of mesenchymal genes. In fact, OVOL2 alone was able to induce the transcriptional program of CECs in neural progenitor cells (NPCs) through repression of mesenchymal genes as well as activation of epithelial genes. Our data suggest that the difference between the transcriptional programs of surface ectoderm-derivatives and neuroectoderm-derivatives is regulated in part by the reciprocally-repressive mechanism between epithelial and mesenchymal genes that is seen in epithelial-to-mesenchymal transition.
Project description:In development, embryonic ectoderm differentiates into several lineages including neuroectoderm and surface ectoderm, through the mechanism largely unclear. Here we report that OVOL2 is required for the transcriptional program of corneal epithelium cell(CEC)s, a derivative of surface ectoderm, and it might regulates the differential transcriptional programs between the two lineages. By a functional screening, we identified transcription factors (TFs) maintaining human CECs. OVOL2 was necessary to maintain the transcriptional program in CECs, particularly through repressing expression of mesenchymal genes. OVOL2 combined with several TFs were able to activate the transcriptional program of CECs in fibroblasts, accompanied by induction of chromatin landscape. Moreover, our analysis revealed that neuroectoderm derivatives express some of mesenchymal genes. In fact, OVOL2 alone was able to induce the transcriptional program of CECs in neural progenitor cells (NPCs) through repression of mesenchymal genes as well as activation of epithelial genes. Our data suggest that the difference between the transcriptional programs of surface ectoderm-derivatives and neuroectoderm-derivatives is regulated in part by the reciprocally-repressive mechanism between epithelial and mesenchymal genes that is seen in epithelial-to-mesenchymal transition.
Project description:In development, embryonic ectoderm differentiates into several lineages including neuroectoderm and surface ectoderm, through the mechanism largely unclear. Here we report that OVOL2 is required for the transcriptional program of corneal epithelium cell(CEC)s, a derivative of surface ectoderm, and it might regulates the differential transcriptional programs between the two lineages. By a functional screening, we identified transcription factors (TFs) maintaining human CECs. OVOL2 was necessary to maintain the transcriptional program in CECs, particularly through repressing expression of mesenchymal genes. OVOL2 combined with several TFs were able to activate the transcriptional program of CECs in fibroblasts, accompanied by induction of chromatin landscape. Moreover, our analysis revealed that neuroectoderm derivatives express some of mesenchymal genes. In fact, OVOL2 alone was able to induce the transcriptional program of CECs in neural progenitor cells (NPCs) through repression of mesenchymal genes as well as activation of epithelial genes. Our data suggest that the difference between the transcriptional programs of surface ectoderm-derivatives and neuroectoderm-derivatives is regulated in part by the reciprocally-repressive mechanism between epithelial and mesenchymal genes that is seen in epithelial-to-mesenchymal transition.
Project description:In development, embryonic ectoderm differentiates into several lineages including neuroectoderm and surface ectoderm, through the mechanism largely unclear. Here we report that OVOL2 is required for the transcriptional program of corneal epithelium cell(CEC)s, a derivative of surface ectoderm, and it might regulates the differential transcriptional programs between the two lineages. By a functional screening, we identified transcription factors (TFs) maintaining human CECs. OVOL2 was necessary to maintain the transcriptional program in CECs, particularly through repressing expression of mesenchymal genes. OVOL2 combined with several TFs were able to activate the transcriptional program of CECs in fibroblasts, accompanied by induction of chromatin landscape. Moreover, our analysis revealed that neuroectoderm derivatives express some of mesenchymal genes. In fact, OVOL2 alone was able to induce the transcriptional program of CECs in neural progenitor cells (NPCs) through repression of mesenchymal genes as well as activation of epithelial genes. Our data suggest that the difference between the transcriptional programs of surface ectoderm-derivatives and neuroectoderm-derivatives is regulated in part by the reciprocally-repressive mechanism between epithelial and mesenchymal genes that is seen in epithelial-to-mesenchymal transition.
Project description:The homeostasis of the transparent corneal epithelium in the eye is maintained by the proliferation and differentiation of limbal stem cells that possess the proper cell fate. A potential disease mechanism underlying corneal opacity has been proposed to be limbal stem cells acquiring the cell fate of keratinocytes in the non-transparent epidermis. In this study, we performed a multi-omics analysis of human limbal stem cells derived from the cornea and keratinocytes from the epidermal stratum basale and characterized the similar yet distinct molecular signatures of these cells. By gene regulatory network analysis, we identified cell fate defining transcription factors and their regulatory hierarchy that are shared by the two cell types and those that regulate specific epithelial programs. Our findings indicate that shared transcription factors often regulate limbal stem cell-specific transcription factors. Single-cell RNA-seq analysis of the cornea and the epidermis confirms the shared and specific transcription factor expression patterns in the stem cells of these tissues. Finally, we showed that genes associated with corneal opacity can cooperatively be targeted by the shared and limbal stem cell-specific transcription factors. By characterizing molecular signatures, our study uncovers the distinct regulatory circuitry controlling limbal stem cell fates and corneal opacity.
Project description:The homeostasis of the transparent corneal epithelium in the eye is maintained by the proliferation and differentiation of limbal stem cells that possess the proper cell fate. A potential disease mechanism underlying corneal opacity has been proposed to be limbal stem cells acquiring the cell fate of keratinocytes in the non-transparent epidermis. In this study, we performed a multi-omics analysis of human limbal stem cells derived from the cornea and keratinocytes from the epidermal stratum basale and characterized the similar yet distinct molecular signatures of these cells. By gene regulatory network analysis, we identified cell fate defining transcription factors and their regulatory hierarchy that are shared by the two cell types and those that regulate specific epithelial programs. Our findings indicate that shared transcription factors often regulate limbal stem cell-specific transcription factors. Single-cell RNA-seq analysis of the cornea and the epidermis confirms the shared and specific transcription factor expression patterns in the stem cells of these tissues. Finally, we showed that genes associated with corneal opacity can cooperatively be targeted by the shared and limbal stem cell-specific transcription factors. By characterizing molecular signatures, our study uncovers the distinct regulatory circuitry controlling limbal stem cell fates and corneal opacity.
Project description:Dr. Panjwani's laboratory is focusing on the mechanism by which galectins-3 and 7 mediate corneal epithelial cell migration. We are currently performing studies to: (i) identify and characterize the corneal epithelial cell surface and extracellular matrix (ECM) molecules which serve as counterreceptors of galectin-3 and -7, to establish whether the lectins modulate corneal epithelial cell migration by binding to well known integrins, growth factor receptors, and/or ECM molecules and (ii) determine whether galectin-3 mediates corneal epithelial cell migration indirectly by modulating the expression of key adhesion and/or signal transduction molecules by using small interfering RNA, cDNA microarrays and glycogene arrays. We have prepared three independent preparations of total RNA of corneal epithelial cells from WT mice (total six samples) for analysis of glycogene expression. Samples are Normal Cornea (Left eye) and Laser ablation + 16-18 hours healing (right eye)