Project description:The genetic daignosis of a pediatric patient with primary symptoms bilateral cataracts, alopecia and microdontia could not be obtained through standard genetic tests. We sought to obtain the diagnosis of this rare syndrome through RNA-seq of the cataract lens against an age-matched donor lens.
Project description:Although majority of the genes linked to pediatric cataract exhibit lens fiber cell-enriched expression, our understanding of gene regulation in these cells is limited to function of just eight transcription factors and largely in the context of crystallins. Here, we identify small Maf transcription factors MafG and MafK as regulators of several non-crystallin human cataract genes in fiber cells and establish their significance to cataract. We applied a bioinformatics tool for cataract gene discovery iSyTE to identify MafG and its co-regulators in the lens, and generated various null-allelic combinations of MafG:MafK mouse mutants for phenotypic and molecular analysis. By age 4-months, MafG-/-:MafK+/- mutants exhibit lens defects that progressively develop into cataract. High-resolution phenotypic characterization of MafG-/-:MafK+/- lens reveals severe defects in fiber cells, while microarrays-based expression profiling identifies 97 differentially regulated genes (DRGs). Integrative analysis of MafG-/-:MafK+/- lens-DRGs with 1) binding-motifs and genomic targets of small Mafs and their regulatory partners, 2) iSyTE lens-expression data, and 3) interactions between DRGs in the String database, unravels a detailed small Maf regulatory network in the lens, several nodes of which are linked to human cataract. This analysis prioritizes 36 highly promising candidates from the original 97 DRGs. Significantly, 8/36 (22%) DRGs are associated with cataracts in human (GSTO1, MGST1, SC4MOL, UCHL1) or mouse (Aldh3a1, Crygf, Hspb1, Pcbd1), suggesting a multifactorial etiology that includes elevation of oxidative stress. These data identify MafG and MafK as new cataract-associated candidates and define their function in regulating largely non-crystallin genes linked to mouse and human cataract. Microarray comparision of lenses from mixed background (129Sv/J, C57BL/6J, and ICR) control (MafG+/-:MafK+/-; no-cataract) and compound (MafG-/-:MafK+/-; cataract) mouse mutants
Project description:Ocular lens development entails epithelial to fiber cell differentiation, defects in which cause congenital cataract. We report the first single-cell multiomic atlas of lens development, leveraging snRNA-seq, snATAC-seq, and CUT&RUN-seq to discover novel mechanisms of cell fate determination and cataract-linked regulatory networks. A comprehensive profile of cis- and trans-regulatory interactions, including for the cataract-linked transcription factor MAF, is established across a temporal trajectory of fiber cell differentiation. Further, we divulge a conserved epigenetic paradigm of cellular differentiation, defined by progressive loss of H3K27 methylation writer Polycomb repressive complex 2 (PRC2). PRC2 localizes to heterochromatin domains across master-regulator transcription factor gene bodies, suggesting it safeguards epithelial cell fate. Moreover, we demonstrate that FGF hyper-stimulation in vivo leads to MAF network activation and the emergence of novel lens cell states. Collectively, these data depict a comprehensive portrait of lens fiber cell differentiation, while defining regulatory effectors of cell identity and cataract formation.
Project description:Ocular lens development entails epithelial to fiber cell differentiation, defects in which cause congenital cataract. We report the first single-cell multiomic atlas of lens development, leveraging snRNA-seq, snATAC-seq, and CUT&RUN-seq to discover novel mechanisms of cell fate determination and cataract-linked regulatory networks. A comprehensive profile of cis- and trans-regulatory interactions, including for the cataract-linked transcription factor MAF, is established across a temporal trajectory of fiber cell differentiation. Further, we divulge a conserved epigenetic paradigm of cellular differentiation, defined by progressive loss of H3K27 methylation writer Polycomb repressive complex 2 (PRC2). PRC2 localizes to heterochromatin domains across master-regulator transcription factor gene bodies, suggesting it safeguards epithelial cell fate. Moreover, we demonstrate that FGF hyper-stimulation in vivo leads to MAF network activation and the emergence of novel lens cell states. Collectively, these data depict a comprehensive portrait of lens fiber cell differentiation, while defining regulatory effectors of cell identity and cataract formation.
Project description:Ocular lens development entails epithelial to fiber cell differentiation, defects in which cause congenital cataract. We report the first single-cell multiomic atlas of lens development, leveraging snRNA-seq, snATAC-seq, and CUT&RUN-seq to discover novel mechanisms of cell fate determination and cataract-linked regulatory networks. A comprehensive profile of cis- and trans-regulatory interactions, including for the cataract-linked transcription factor MAF, is established across a temporal trajectory of fiber cell differentiation. Further, we divulge a conserved epigenetic paradigm of cellular differentiation, defined by progressive loss of H3K27 methylation writer Polycomb repressive complex 2 (PRC2). PRC2 localizes to heterochromatin domains across master-regulator transcription factor gene bodies, suggesting it safeguards epithelial cell fate. Moreover, we demonstrate that FGF hyper-stimulation in vivo leads to MAF network activation and the emergence of novel lens cell states. Collectively, these data depict a comprehensive portrait of lens fiber cell differentiation, while defining regulatory effectors of cell identity and cataract formation.
Project description:Pseudoexfoliation syndrome (PEXS) is a late-onset disorder in which fibrillar material accumulates at abnormally high concentrations mainly in the anterior segment of the eye. PEXS is the most common cause of secondary glaucoma, which can ultimately lead to blindness and is associated with a higher risk of cataract and serious complications following different types of intraocular surgery. Although PEXS clearly has a genetic component, it remains poorly explored. In our genome-wide association study, we searched for an association of genetic variants with this disorder among older Poles with PEXS without glaucoma.
Project description:Purpose of arrays were to determine what the effect of deletion of Mbtps1 gene was on gene expression of osteocytes in bone in vivo. DMP1 cre driver was used to delete the Mbtps1 gene in osteocytes and osteoblasts in bone. We then isolated osteocyte enriched bone particles from 40 week old male mice to determine the effect of this deletion on gene expression. We have previously shown that Mbtps1 is needed for transcription of Phex, DMP1, and MEPE genes in osteoblasts in culture. Arrays showed these genes were reduced as expected in osteocytes in vivo. Controls represent osteocyte enriched bone from 40 week old littermates. Also, as expected, Mbtps1 expression was reduced in these knockout mice
Project description:Alopecia areata (AA) is a prevalent disease associated with major emotional distress, and lacks effective, safe therapeutics for patients with extensive hair loss. This is the first report of hair regrowth with specific cytokine antagonism, in three patients with extensive hair loss ranging from 40% scalp involvement to alopecia universalis. Ustekinumab, an IL-12/23p40 antagonist that is highly effective in psoriasis, showed impressive ability to induce hair regrowth, coupled with suppression of inflammatory pathways and upregulation of hair keratins. Our report suggests that extensive AA is reversible using targeted treatments, opening the door for specific cytokine antagonism for this debilitating disease.
Project description:Celf1 germline or conditional deletion mouse mutants exhibit fully penetrant lens defects including cataract. To gain insight into gene expression changes underlying these lens defects, microarray comparison was performed for lenses obtained from control and Celf1 conditional deletion mutant mice.