Enhancer activation by FGF signalling during otic induction
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ABSTRACT:
ORGANISM(S): Gallus gallus
PROVIDER: GSE137664 | GEO | 2019/09/19
REPOSITORIES: GEO
Similar Datasets
Project description:The inner ear develops from a patch of thickened cranial ectoderm adjacent to the hindbrain called the otic placode. Studies in a number of vertebrate species suggest that the initial steps in induction of the otic placode are regulated by members of the Fibroblast Growth Factor (FGF) family, and that inhibition of FGF signaling can prevent otic placode formation. To better understand the genetic pathways activated by FGF signaling during otic placode induction, we performed microarray experiments to estimate the proportion of chicken otic placode genes that can be up-regulated by the FGF pathway in a simple culture model of otic placode induction. Surprisingly, we find that FGF is only sufficient to induce about 15% of chick otic placode-specific genes in our experimental system. However, pharmacological blockade of the FGF pathway in cultured chick embryos showed that although FGF signaling was not sufficient to induce the majority of otic placode-specific genes, it was still necessary for their expression in vivo. These inhibitor experiments further suggest that the early steps in otic placode induction regulated by FGF signaling occur through the MAP kinase pathway. Although our work suggests that FGF signaling is necessary for otic placode induction, it demonstrates that other unidentified signaling pathways are required to co-operate with FGF signaling to induce the full otic placode program. 8 samples were analyzed. These contain two replicates of each of the following four catergories: Otic ectoderm, Non-Otic (lateral) ectoderm, Trigeminal Ectoderm cultured - FGF, Trigeminal Ectoderm cultured + FGF
2012-12-12 | E-GEOD-42845 | biostudies-arrayexpress
Project description:The inner ear develops from a patch of thickened cranial ectoderm adjacent to the hindbrain called the otic placode. Studies in a number of vertebrate species suggest that the initial steps in induction of the otic placode are regulated by members of the Fibroblast Growth Factor (FGF) family, and that inhibition of FGF signaling can prevent otic placode formation. To better understand the genetic pathways activated by FGF signaling during otic placode induction, we performed microarray experiments to estimate the proportion of chicken otic placode genes that can be up-regulated by the FGF pathway in a simple culture model of otic placode induction. Surprisingly, we find that FGF is only sufficient to induce about 15% of chick otic placode-specific genes in our experimental system. However, pharmacological blockade of the FGF pathway in cultured chick embryos showed that although FGF signaling was not sufficient to induce the majority of otic placode-specific genes, it was still necessary for their expression in vivo. These inhibitor experiments further suggest that the early steps in otic placode induction regulated by FGF signaling occur through the MAP kinase pathway. Although our work suggests that FGF signaling is necessary for otic placode induction, it demonstrates that other unidentified signaling pathways are required to co-operate with FGF signaling to induce the full otic placode program.
2012-12-12 | GSE42845 | GEO
Project description:Enhancer activation by FGF signalling during otic induction
| PRJNA566175 | ENA
Project description:Stem cells, with their potential to generate different lineages, could offer a solution by replacing damaged or lost cells within the inner ear. We have shown that human embryonic stem cells can be induced to differentiate into otic progenitors, and then into hair cell-like cells and neurons that display expected electrophysiological properties. More importantly, once these otic progenitors are transplanted into animals with induced hearing loss, they differentiate and elicit a significant recovery of auditory function. The generation of otic progenitors is triggered by FGF signalling. In this dataset we have analysed the global gene expression profile of undifferentiated hESCs and compared with cultures that have been treated with FGF3 and 10, the two ligands involved in otic induction, or cultures that have been allowed to differentiate under basal conditions without FGF (DFNB).
2012-09-12 | GSE36754 | GEO
Project description:Stem cells, with their potential to generate different lineages, could offer a solution by replacing damaged or lost cells within the inner ear. We have shown that human embryonic stem cells can be induced to differentiate into otic progenitors, and then into hair cell-like cells and neurons that display expected electrophysiological properties. More importantly, once these otic progenitors are transplanted into animals with induced hearing loss, they differentiate and elicit a significant recovery of auditory function. The generation of otic progenitors is triggered by FGF signalling. In this dataset we have analysed the global gene expression profile of undifferentiated hESCs and compared with cultures that have been treated with FGF3 and 10, the two ligands involved in otic induction, or cultures that have been allowed to differentiate under basal conditions without FGF (DFNB). Global gene expression profiles were obtained from hESC lines H14, Shef3 and Shef1 by hybridizing samples from undifferentiated cells (Day 0) and cells exposed to either FGF3+10- or DFNB medium for 14 days. Three experimental conditions are therefore produced: hESC, FGF3+10 and DFNB.
2012-09-12 | E-GEOD-36754 | biostudies-arrayexpress
Project description:The otic placode, from which the inner ear develops, initially forms as a thickened ectodermal patch adjacent to the dorsolateral hindbrain. Induction of otic placodal cells from human pluripotent stem cells (hPSCs) provides a robust approach to investigation of otic development. However, attempts to recapitulate otic lineage specification from hPSCs by stepwise differentiation methods have had limited success. One possible reason is that the role of signaling pathways in otic cell differentiation is not fully understood. Here, we developed a novel differentiation system involving use of suspension culture (3D floating culture) in combination with signaling factors for generating otic placodal cells via stepwise differentiation of hPSCs. We demonstrate that hPSC-derived pre-placodal cells acquired the potential to differentiate into posterior placodal cells after fibroblast growth factor 2 (FGF2) and retinoic acid (RA) treatment. Subsequent activation of WNT signaling following posterior placode specification induced differentiation of SIX1+/PAX8+/SOX2+ otic placodal cells. qPCR analysis showed that WNT activation increased expression of otocyst markers, including PAX8, PAX2, DLX5 and FBXO2. Moreover, induced otic cells exhibited similar gene expression patterns to the ventral and medial portions of the otocyst that give rise to the sensory epithelium of the inner ear. Collectively, our results indicate a critical role for FGF2, RA, and WNT signaling for the in vitro differentiation of the otic cell lineage from hPSCs. Our new culture system paves the way for improved modeling of early human inner ear development and will be of value to studies on the further differentiation of sensory epithelial cells.
2022-02-01 | GSE175998 | GEO
Project description:Mutations in the chromatin remodeling enzyme CHD7 cause CHARGE syndrome, which affects multiple organs including the inner ear. We investigated how CHD7 mutations affect otic development in human inner ear organoids. We found loss of CHD7 or its chromatin remodeling activity leads to complete absence of hair cells and supporting cells, which can be explained by dysregulation of key otic development-associated genes in mutant otic progenitors. Further analysis of the mutant otic progenitors suggested that CHD7 can regulate otic genes through a chromatin remodeling-independent mechanism. Results from transcriptome profiling of hair cells revealed disruption of deafness gene expression as a potential underlying mechanism of CHARGE-associated sensorineural hearing loss. Notably, co-differentiating CHD7 knockout and wild-type cells in chimeric organoids partially rescued mutant phenotypes by restoring otherwise severely dysregulated otic genes. Taken together, our results suggest that CHD7 plays a critical role in regulating human otic lineage differentiation and deafness gene expression.
2022-07-21 | GSE208585 | GEO
Project description:Previously FGF signalling has been shown to specify otic fate from multipotent pre-placodal ectoderm. Though many FGF target genes have been identified in subsequent studies, none of them is sufficient to induce otic lineage. Profiling and analysing the transcriptome and epigenomical signature during otic specification, we predicted and confirmed Sox8 as an otic master regulator, able to specify otic fate in the pre-placodal ectoderm. This is achieved by activating the expression of otic identity markers and compromising the fate towards lens and trigeminal ganglion. In the combat to differentiate ESCs/iPSCs or convert other cell lineage into otic lineage, our discovery may add another weaponry to tame these cells towards otic cells.
2022-08-01 | GSE102825 | GEO
Project description:A large number of congenital hearing loss cases have an unknown genetic etiology. So far, transcriptomic approaches have successfully identified many candidate regulators of otic development, little is known about the abundance of their protein products during the development of the inner eat. Herein we used a multiplexed quantitative mass spectrometry-based proteomic approach to determine temporal trends in protein abundances during inner ear (otic) development in Xenopus. Wild type Xenopus embryos were cultured to larval stages and their otic tissues were manually dissected at five stages that represent that represent key transitions in otic morphology. The samples were processed using a bottom-up proteomic workflow and analyzed using LC-MS3.The analysis revealed dynamic expression of proteins related to cytoskeletal regulation, integrin signaling, and the extracellular matrix as inner ear structures developed. We correlated the dynamically regulated proteins in our dataset with previously published putative downstream targets of syndromic hearing loss genes SIX1 and CHD7 to identify novel candidate genes for congenital hearing loss.
2023-10-24 | PXD041991 | Pride
Project description:The molecular characterization of early stages of human inner ear development is limited by the difficulty in accessing samples at early gestational stages. Some aspects of inner ear morphogenesis can be recapitulated using pluripotent stem cell directed differentiation in inner ear organoids (IEOs). Once validated and benchmarked, these models could provide a unique tool to complement and refine our understanding of human otic differentiation and could be used to model developmental defects.Here we provide a first characterization of early human embryonic otocyst development and compare the primary tissue to the iPSC-derived inner ear cell types. Multiplex immunostaining and single cell RNA sequencing were used to characterize human iPSC-derived IEOs at 3 key developmental steps, providing a new and unique signature of in vitro derived otic- placode, epithelium, neuroblasts and sensory epithelia. The expression and localization of key markers were further evaluated in human embryos. We show that the otic placode derived in vitro (day 8-12) matches marker expression of Carnegie Stage (CS) 11 embryos, and subsequently (day 20-40) gives rise to otic epithelia and neuroblasts comparable to the CS13 embryonic stage. Differentiation of sensory epithelia, including supporting cells and hair cells, starts in vitro at day 50-60 of culture. The maturity of these cells is equivalent to vestibular sensory epithelia at week 10 or cochlear tissue at week 12 of development, prior to functional onset. Taken together these data indicates that the current state of the art protocol enables the specification of bona fide otic tissue, supporting further application of IEOs to model inner ear biology and disease
2023-08-22 | GSE229148 | GEO