Project description:Cleft palate is a common disorder of development resulting from failure of growth, migration, elevation, and osteogenic fusion of embryonic cranial neural crest-derived palatal shelves. Despite progress in recent decades, the molecular pathways involved in this failure are not well understood. Here, we present a multimodal, spatiotemporal transcriptomic profiling of the developing palate through integrated, unbiased single-cell and bulk RNA-sequencing and multiplexed in situ mRNA mapping of osteogenic cell lineages. We then show that loss of Pax9, a critical transcription factor orchestrator of Wnt signaling in palate development, results in increased expression of sclerostin (Sost), a known antagonist of Wnt signaling. Finally, we reveal that a single dose of sclerostin-neutralizing monoclonal antibody restores Wnt signaling and corrects cleft palate defects in utero in Pax9-/- mouse embryos.
Project description:Cleft palate is a common disorder of development resulting from failure of growth, migration, elevation, and osteogenic fusion of embryonic cranial neural crest-derived palatal shelves. Despite progress in recent decades, the molecular pathways involved in this failure are not well understood. Here, we present a multimodal, spatiotemporal transcriptomic profiling of the developing palate through integrated, unbiased single-cell and bulk RNA-sequencing and multiplexed in situ mRNA mapping of osteogenic cell lineages. We then show that loss of Pax9, a critical transcription factor orchestrator of Wnt signaling in palate development, results in increased expression of sclerostin (Sost), a known antagonist of Wnt signaling. Finally, we reveal that a single dose of sclerostin-neutralizing monoclonal antibody restores Wnt signaling and corrects cleft palate defects in utero in Pax9-/- mouse embryos.
Project description:The Chinese sturgeon (Acipenser sinensis) is anadromous fish distributed in Yangtze River and East China Sea. In this study, we reported cleft-palate Chinese sturgeons in artificial population for the first time. In order to explore the genetic basis of palate malformation in A. sinensis, Illumina RNA-seq technology was used to analyze the transcriptome data of normal and cleft-palate individuals in farmed Chinese sturgeons. Raw reads were obtained and assembled into 808,612 unigenes, with an average length of 509.33 bp and an N50 of 574 bp. Sequence similarity analyses against four public databases (Nr, Uniprot, KEGG and COGs) found 158,642 unigenes that can be annotated. GABAergic synapse and TGF-β signal pathway were the most two enriched pathways with high Richfactor in the analyses of different expressed genes. In these two signal pathways, six genes (GABRA4, GS, GNS, S6K, PITX2, and BMP8) were found as cleft-palate genes in Chinese sturgeon. These findings contribute to our understanding of the genetic basis of cleft palate in sturgeon, while simultaneously adding to our knowledge about craniofacial development.
Project description:Tamoxifen (TAM), a widely-used drug in treating breast cancer, has been reported to be associated with craniofacial defects including micrognathia and cleft palate in humans. However, the exact effects of TAM on the developing palate remain unclear. In the present study, we conclude that excess TAM exposure causes cleft palate defect in mice by regulating MAPK pathways, which implicates the importance of tightly regulated MAPK signaling in palate development and provides a basis for further exploration of the molecular etiology of cleft palate defects caused by environmental factors.
Project description:The overall goal of this project is to investigate the role of TGF-beta signaling in palate development in order to discover candidate therapeutics for preventing and treating congenital birth defects. Here, we conducted gene expression profiling of embryonic palatal tissue from wild type mice as well as those with a neural crest specific conditional inactivation of the Tgfbr2 gene. The latter mice provide a model of cleft palate formation. To investigate the mechanism of cleft palate resulting from mutations in TGFBR2, we analyzed neural crest specific conditional inactivation of Tgfbr2 in mice (Tgfbr2fl/fl;Wnt1-Cre). We performed microarray analyses using the palatal tissue of Tgfbr2fl/fl;Wnt1-Cre mice at embryonic day E13.5 (prior to palatal fusion, n=6 per genotype) and E14.5 (during palatal fusion, n=5 per genotype) to examine the genes regulated by Tgf-beta during palate formation.
Project description:ChIP-Sequencing on Meis2-HA in E12.5 palate, to identify Meis2 binding chromatin regions and target genes. Haploinsufficiency of MEIS2 is associated with cleft palate in humans and Meis2 inactivation leads to abnormal palate development in mice, implicating an essential role for Meis2 in palate development. However, its functional mechanisms remain unknown. In this study, we found widespread Meis2 expression in the developing palate in mice. Meis2 inactivation by Wnt1Cre in cranial neural crest cells led to the cleft of the secondary palate. Importantly, about half of Wnt1Cre;Meis2f/f mice exhibited submucous cleft, providing an excellent model for studying palatal bone formation and patterning. Consistent with a complete absence of the palatal bones, integrative analyses of Meis2 ChIP-seq, RNA-seq, and ATAC-seq results identified key osteogenic genes that are regulated directly by Meis2, indicating the fundamental role of Meis2 in palatal osteogenesis. De novo motif analysis discovered that the Meis2-bound regions possess highly enriched binding motifs of several key osteogenic transcription factors particularly Shox2. Comparison of Meis2 and Shox2 ChIP-seq analyses further revealed a genome-wide co-occupancy, in addition to their co-localization in the developing palate and physical interaction, suggesting that Shox2 and Meis2 act as partners. However, while Shox2 is required for proper palatal bone formation and is a direct downstream target of Meis2, Shox2 overexpression failed to rescue the palatal bone defects in Meis2 mutant background. These results, together with the facts that Meis2 expression is associated with high osteogenic potential and is required for the chromatin accessibility of osteogenic genes, support a vital function of Meis2 in setting up the ground state for palatal osteogenesis.
Project description:Cleft palate is among the most common structural birth defects in humans. Previous studies have shown that mutations in FOXF2 are associated with cleft palate in humans and mice and that Foxf2 acts in a Shh-Foxf-Fgf18-Shh molecular network controlling palatal shelf growth. In this study, we generated mice carrying 3xFLAG epitope-tagged endogenous Foxf2 protein using the CRISPR/Cas9-mediated genome editing technology and characterized genome-wide Foxf2 binding sites in the developing palatal shelves using chromatin immunoprecipitation and genome sequencing (ChIP-seq). By combined analysis of ChIP-seq and RNA-seq datasets we identified a large list of Foxf2 target genes. Further analyses demonstrate that Foxf2 directly regulate expression of several genes encoding ECM or ECM modifiers during palate development. Moreover, our ChIP-seq and RNA-seq datasets provide an excellent resource for comprehensive understanding of the molecular network controlling palate development.
Project description:Cleft palate is a common congenital anomaly with a live birth prevalence estimated to be 1:2500 live births, that results from failure of growth, elevation, adhesion and/or fusion of the palatal shelves during embryogenesis. Mutations in the gene encoding the transcription factor p63 result in cleft palate in humans and mice. To study the roles of P63 in periderm migration and medial edge epithelia in mice sub-mucous cleft palate, ÎNp63alpha was ectopically expressed in the palatal epithelia using a transgenic approach.
Project description:We use ATAC-seq to identify chromatin accessibility in the palatal mesenchyme of wildtype and Wnt1Cre;Meis2f/f mice at E12.5. Haploinsufficiency of MEIS2 is associated with cleft palate in humans and Meis2 inactivation leads to abnormal palate development in mice, implicating an essential role for Meis2 in palate development. However, its functional mechanisms remain unknown. In this study, we found widespread Meis2 expression in the developing palate in mice. Meis2 inactivation by Wnt1Cre in cranial neural crest cells led to the cleft of the secondary palate. Importantly, about half of Wnt1Cre;Meis2f/f mice exhibited submucous cleft, providing an excellent model for studying palatal bone formation and patterning. Consistent with a complete absence of the palatal bones, integrative analyses of Meis2 ChIP-seq, RNA-seq, and ATAC-seq results identified key osteogenic genes that are regulated directly by Meis2, indicating the fundamental role of Meis2 in palatal osteogenesis. De novo motif analysis discovered that the Meis2-bound regions possess highly enriched binding motifs of several key osteogenic transcription factors particularly Shox2. Comparison of Meis2 and Shox2 ChIP-seq analyses further revealed a genome-wide co-occupancy, in addition to their co-localization in the developing palate and physical interaction, suggesting that Shox2 and Meis2 act as partners. However, while Shox2 is required for proper palatal bone formation and is a direct downstream target of Meis2, Shox2 overexpression failed to rescue the palatal bone defects in Meis2 mutant background. These results, together with the facts that Meis2 expression is associated with high osteogenic potential and is required for the chromatin accessibility of osteogenic genes, support a vital function of Meis2 in setting up the ground state for palatal osteogenesis.
Project description:Deficiency of the transcription factor Cited2 in mice results in cardiac malformation, adrenal agenesis, neural tube, placental defects, and partially penetrant left-right patterning defects resulting from an abnormal Nodal->Pitx2c pathway. Here we show that a maternal high-fat diet more than doubles the penetrance of laterality defects and, surprisingly, induces palatal clefting in Cited2 deficient embryos. Both maternal diet and Cited2 deletion reduce embryo weight and kidney and thymus volume. Expression profiling identified 40 embryonic transcripts including Pitx2 that were significantly affected by embryonic genotype-maternal diet interaction. We show that a high-fat diet reduces Pitx2c levels >2 fold in Cited2 deficient embryos and that Pitx2c deficiency results in cleft palate. Taken together, these results define a novel interaction between maternal high-fat diet and embryonic Cited2 deficiency that affects Pitx2c expression and results in abnormal laterality and cleft palate.