The epigenetic landscape controlled by p63 during epidermal keratinocyte differentiation
ABSTRACT: Transcription factor p63 is a key regulator of epidermal keratinocyte proliferation and differentiation. Heterozygous mutations of TP63 encoding p63 cause a spectrum of developmental disorders. EEC syndrome is caused by point mutations in the p63 DNA-binding domain, and manifests ectodermal dysplasia with defects in the epidermis and epidermal related appendages, limb malformation and cleft lip/palate. Five hotspot mutations affecting amino acids, R204, R227, R279, R280 and R304, have been found in approximately 90% of the EEC population. Although the role of p63 in normal epidermal development and differentiation has been demonstrated, the molecular mechanism by which p63 mutations cause the epidermal phenotype in diseases is not yet understood. We previously reported that EEC patient keratinocytes cannot fully differentiate towards terminal stratification in both 2D and 3D cellular models. In this study, EEC patient keratinocytes carrying three hotspot... (for more see dbGaP study page.)
Project description:Schimke immuno-osseous dysplasia (SIOD) is a multisystemic disorder caused by biallelic mutations in SWI/SNF-related matrix associated actin-dependent regulator of chromatin, subfamily A-like protein 1 (SMARCAL1). Changes in gene expression appear to underlie the immunodeficiency and arteriosclerosis of SIOD; therefore, we hypothesized that SMARCAL1 deficiency alters renal gene expression to cause the focal segmental glomerulosclerosis (FSGS) of SIOD, and that these gene expression alterations would be comparable to those observed in isolated FSGS. We tested this hypothesis by gene expression microarray analysis. Overall design: Comparison of gene expression between the cultured primary renal proximal tubular cells of a Schimke immuno-osseous dysplasia (SIOD) patient and of a patient with non-SIOD-associated FSGS
Project description:Transcription factor paralogs may share a common role (e.g. Hox) in staged or overlapping expression in specific tissues. In other examples, members have distinct roles in a range of embryologic, differentiation or response pathways (e.g. Tbx, Pax). For the Interferon Regulatory Factor (IRF) family of transcription factors, mice deficient in Irf1, Irf2, Irf3, Irf4, Irf5, Irf7, Irf8 or Irf9, have defects in the immune response but display no embryologic abnormalities. Mice deficient for Irf6 have not been reported, but in humans, mutations in IRF6 cause two Mendelian orofacial clefting syndrome, and genetic variation in IRF6 confers risk for isolated cleft lip and palate. Mice deficient for Irf6 have abnormal skin, limb and craniofacial development. Histological and gene expression analyses indicate that the primary defect is in keratinocyte differentiation and proliferation. This study describes a novel role for an IRF family member in epidermal development. Experiment Overall Design: Skin from E17.5 mice was removed and flash frozen for RNA extraction and hybridization on Affymetrix microarrays.
Project description:Schimke immuno-osseous dysplasia (SIOD) is a multisystemic disorder caused by biallelic mutations in SWI/SNF-related matrix associated actin-dependent regulator of chromatin, subfamily A-like protein 1 (SMARCAL1). Changes in gene expression appear to underlie the immunodeficiency and arteriosclerosis of SIOD; therefore, we hypothesized that SMARCAL1 deficiency alters renal gene expression to cause the focal segmental glomerulosclerosis (FSGS) of SIOD. We tested this hypothesis by transcriptome analysis and quantitative reverse transcription PCR (qRT-PCR) of an SIOD patient kidney, a genetic screen and immunofluorescence. These showed increased expression of genes in the Wnt and Notch signaling pathways in an SIOD patient kidney, interaction of Marcal1 with genes encoding components of the Wnt and Notch signaling pathways, and increased levels of unphosphorylated b-catenin and Notch1 intracellular domain (NICD) in the glomeruli of SIOD patient kidneys. Given that increased Wnt and Notch activity are established causes of FSGS, we hypothesize that SMARCAL1 deficiency increases the activity of one or both of these pathways to cause the renal disease of most SIOD patients. Overall design: Comparison of mRNA levels between the kidney tissue of a Schimke immuno-osseous dysplasia (SIOD) patient and an unaffected control
Project description:Mutations in the transcription factor p63 underlie of a series of human malformation syndromes which are defined by a combination of epidermal, limb and craniofacial abnormalities including cleft lip and palate. Transcription profiling was performed to determine the role of p63 in vivo mouse palatal shelves. Microarray analysis was done of palatal shelves dissected from E14.0 wild-type versus p63-null mouse embryos.
Project description:Mutations in the transcription factor p63 underlie of a series of human malformation syndromes which are defined by a combination of epidermal, limb and craniofacial abnormalities including cleft lip and palate. Transcription profiling was performed to determine the role of p63 in vivo mouse palatal shelves. RNA-seq analysis was done of palatal shelves dissected from E10.5, E11.5, E12.5, E13.5 and E14.5 mouse embryos.
Project description:Orofacial clefts are one of the most common birth defects, affecting 1-2 per 1000 births, and have a complex etiology. High-resolution array-based comparative genomic hybridization has increased the ability to detect copy number variants that can be causative for complex diseases such as cleft lip and/or palate. Utilizing this technique on 97 non-syndromic cleft lip and palate cases and 43 cases with cleft palate only, we identified a heterozygous deletion of Isthmin 1 in one affected case, as well as a deletion in a second case which removes putative 3' regulatory information. Isthmin 1 is a strong candidate for clefting as it is expressed in orofacial structures derived from the first branchial arch and is also in the same synexpression group as fibroblast growth factor 8 and sprouty RTK signaling antagonist 1a and 2, all of which have been associated with clefting. Copy number variants affecting Isthmin 1 are exceedingly rare in control populations, and Isthmin 1 scores as a likely haploinsufficiency locus. Confirming its role in craniofacial development, knockdown or CRISPR/Cas9-generated mutation of isthmin 1 in Xenopus laevis resulted in mild to severe craniofacial dysmorphologies, with several individuals presenting with median clefts. Moreover, knockdown of isthmin 1 produced decreased expression of LIM homeobox 8, itself a gene associated with clefting, in regions of the face that pattern the maxilla. Our study demonstrates a successful pipeline from copy number variant identification of a candidate gene to functional validation in a vertebrate model system and reveals Isthmin 1 as both a new human clefting locus as well as a key craniofacial patterning gene. Overall design: array-based Comparative Genomic Hybridization (aCGH) of 140 Filipino probands with cleft lip and palate assessed for rare deletions
Project description:Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer and is major cause of cancer mortality and morbidity. It emerges within oral cavity, lip, tongue, floor of the mouth, nasopharynx, palate, gingival and larynx, is common cancer worldwide especially in Southeast Asia and Southern China. Despite of the advancements in the understanding of the HNSCC as the disease, the 5 year survival rate remains unchanged at 50% since last three decades. Factors such as advanced stage presentation of the patient and consequent delay in diagnosis contributes to the bleak scenario. Thus, therefore there is dire need of useful biomarkers that can predict HNSCC in early stages and can serve as prognostic indicators or targets for treatment. In the present study, We used iTRAQ (isobaric tags for relative and absolute quantitation)-based quantitative proteomic approach followed by liquid chromatography and high resolution tandem mass spectrometry (LC-MS/MS) to identify differential proteins from head and neck cancer cell lines.
Project description:Mutations in the RMRP gene are the origin of cartilage-hair hypoplasia. Cartilage-hair hypoplasia is associated with severe dwarfism caused by impaired skeletal development. However, it is not clear why mutations in the RMRP gene lead to skeletal dysplasia. Viperin is a known substrate of RMRP. Since chondrogenic differentiation of the growth plate is required for development of the long bones, we hypothesized that viperin functions as a chondrogenic regulator downstream of RMRP. Viperin protein is expressed throughout the stages of chondrogenic differentiation in vivo. Viperin gene expression is increased during knockdown of Rmrp RNA in the ATDC5 model for chondrogenic differentiation. Viperin is expressed during ATDC5 chondrogenic differentiation. Viperin knockdown reduces, while viperin overexpression increases overall protein secretion, with CXCL10 identified as a potential target via mass spectrometry-proteomics. CXCL10 protein expression is reduced during knockdown and increased during overexpression of viperin and CXCL10 protein expression coincides with viperin expression in ATDC5 chondrogenic differentiation. Viperin knockdown induces, while viperin overexpression reduces TGFβ activity. Furthermore, viperin knockdown conditioned media increases, while viperin overexpression conditioned media reduces chondrogenic differentiation of ATDC5 cells. TGFβ target genes Pai1 and Smad7 are increased during knockdown and reduced during overexpression of viperin. Moreover, TGFβ activity is reduced when differentiating ATDC5 cells are exposed to CXCL10 and, acting as a viperin overexpression mimic, CXCL10 similarly reduces chondrogenic differentiation of ATDC5. Lastly, we show that in CHH patient cells, RMRP expression is reduced and viperin expression is increased, coinciding with reduced chondrogenic differentiation and increased CXCL10 expression, possibly explaining the CHH phenotype. Together our data show that viperin may play a pivotal role in chondrogenic differentiation, with potential consequences for cartilage-hair hypoplasia pathobiology.
Project description:Nonsyndromic clefts of the palate and/or lip are common birth defects arising in about 1/700 live births worldwide. They are caused by multiple genetic and environmental factors, can only be corrected surgically and require complex post-operative care that imposes significant burdens on individuals and society. Our understanding of the molecular networks that control palatogenesis has advanced through studies on mouse genetic models of cleft palate. In particular, the transcription factor Pax9 regulates palatogenesis through the Bmp, Fgf and Shh pathways in mice. But there is still much to learn about Pax9’s relationship with other signaling pathways in this process. Expression analyses and unbiased gene expression profiling studies offer a molecular explanation for the resolution of palatal defects by showing that Wnt and Eda/Edar-related genes are expressed in normal palatal tissues and that the Wnt and Eda/Edar signaling pathway is downstream of Pax9 in palatogenesis. Overall design: E13.5 mouse embryos palate were micro-dissceted, control and mutant samples were seperated and individually lyzed for the RNA extraction.
Project description:We sought to identify Hedgehog-regulated genes in the frontonasal process (FNP) and ventral prosencephalon at GD9.25 in mice, during the initial pathogenesis of cleft lip with or without cleft palate. Overall design: Frontonasal process and underlying ventral prosencephalon tissues were microdissected from GD9.25 (20-24 somite pairs) mouse embryos exposed to vehicle or cyclopamine from GD8.25-9.25. Tissues were pooled by litter to minimize intralitter variability. N=6 vehicle and N=6 cyclopamine pooled litters were included in the analysis.