Project description:PURPOSE: To provide a detailed gene expression profile of the normal postnatal mouse cornea. METHODS: Serial analysis of gene expression (SAGE) was performed on postnatal day (PN)9 and adult mouse (6 week) total corneas. The expression of selected genes was analyzed by in situ hybridization. RESULTS: A total of 64,272 PN9 and 62,206 adult tags were sequenced. Mouse corneal transcriptomes are composed of at least 19,544 and 18,509 unique mRNAs, respectively. One third of the unique tags were expressed at both stages, whereas a third was identified exclusively in PN9 or adult corneas. Three hundred thirty-four PN9 and 339 adult tags were enriched more than fivefold over other published nonocular libraries. Abundant transcripts were associated with metabolic functions, redox activities, and barrier integrity. Three members of the Ly-6/uPAR family whose functions are unknown in the cornea constitute more than 1% of the total mRNA. Aquaporin 5, epithelial membrane protein and glutathione-S-transferase (GST) omega-1, and GST alpha-4 mRNAs were preferentially expressed in distinct corneal epithelial layers, providing new markers for stratification. More than 200 tags were differentially expressed, of which 25 mediate transcription. CONCLUSIONS: In addition to providing a detailed profile of expressed genes in the PN9 and mature mouse cornea, the present SAGE data demonstrate dynamic changes in gene expression after eye opening and provide new probes for exploring corneal epithelial cell stratification, development, and function and for exploring the intricate relationship between programmed and environmentally induced gene expression in the cornea. Keywords: other
Project description:To gain a deeper understanding of the genetic basis of liver repopulation after injury, we utilize an innovative technique to profile the expression changes and chromatin landscape during the regenerative response. We utilize the Fah-/- mouse, a model for hereditary tyrosinemia deficient in fumarylacetoacetate hydrolase (FAH), that undergoes repopulation with FAH-expressing hepatocytes. We employ translating ribosome affinity purification followed by RNA-sequencing (TRAP-seq) and assay for transposase accessible chromatin using sequencing (ATAC-seq) to specifically isolate regenerating hepatocytes and performed high-throughput sequencing to identify the dynamic genomic and epigenomic changes during liver repopulation.
Project description:Dynamic epigenetic changes guide retinal progenitor cells (RPCs) toward diverse neuronal subtypes and Müller glia during retinal development. However, the epigenetic mechanisms that maintain RPC proliferative and neurogenic potential throughout the final stages of retinal cell genesis remain poorly understood. Here, we integrate RNA sequencing and assay for transposase-accessible chromatin sequencing (ATAC-seq) to investigate how mouse RPC stemness is regulated. Our analysis reveals conserved chromatin accessibility and gene expression profiles in mouse RPCs throughout retinal cell genesis. Notably, the histone methyltransferase Setd8, which catalyzes H4K20 monomethylation, remains persistently expressed in RPCs but is barely detectable in adult Müller glia. Setd8 deletion in developing RPCs reduces proliferation, triggers apoptosis, and disrupts retinal laminar organization and ocular axis length. Additionally, Setd8 deficiency impairs the chromatin accessibility that is normally preserved in RPCs, leading to a partial acquisition of a transcriptomic profile associated with terminally differentiated cells. Our study indicates that Setd8 safeguards mouse RPC identity by maintaining RPC-specific chromatin accessibility, thereby ensuring proper retinal development.