Project description:Although intensively studied, the gene networks regulating limb development is still incomplete. Indeed, efforts to decipher the genetic and transcriptional control of limb formation rely mainly on transcriptome approaches obtained from embryos collected 0.5 or 1 day apart from E9.5 to E13.5. This approach identified gene networks tightly regulated during limb morphogenesis as well as novel genes possibly involved in these networks. However, given the complexity and speed of the underlying molecular processes at these stages, relying on time points 1 or even 0.5 day apart limits our ability to capture regulatory changes taking place at a faster pace, and to identify the factors on which they depend. To obtain a comprehensive view of the limb developmental progression at the molecular level, we used the roller system to culture E10.5 and E12.5 mouse embryos over a 6h time window and performed a microarray analysis (Affymetrix GeneChip® Mouse Exon 1.0 ST Arrays) on the collected samples
Project description:Detailed information about stage-specific changes in gene expression is crucial for understanding the gene regulatory networks underlying development and the various signal transduction pathways contributing to morphogenesis. Here, we describe the global gene expression dynamics during early murine limb development, when cartilage, tendons, muscle, joints, vasculature, and nerves are specified and the musculoskeletal system of the limbs is established. We used whole-genome microarrays to identify genes with differential expression at 5 stages of limb development (E9.5 to 13.5), during fore-limb and hind-limb patterning. We found that the onset of limb formation is characterized by an up-regulation of transcription factors, which is followed by a massive activation of genes during E10.5 and E11.5 which tampers off at later time points. Among 3520 genes identified as significantly up-regulated in the limb, we find ~30% to be novel, dramatically expanding the repertoire of candidate genes likely to function in the limb. Hierarchical and stage-specific clustering identified expression profiles that correlate with functional programs during limb development and are likely to provide new insights into specific tissue patterning processes. Here we provide for the first time, a comprehensve analysis of developmentally regulated genes during murine limb development, and provide some novel insights into the expression dynamics governing limb morphogenesis. Fifty- one arrays were analyzed, consisting of whole fore-limb and hind-limb bud RNA (experimental) and whole embryo RNA (reference) samples from E9.5 to E13.5 DPC mouse (FVB strain). Embryos were not pooled to generate samples. Each time point has 3 to 5 biological replicates for limb bud samples, duplicates for whole embryos. Comparisons were made between limb bud samples and whole embryo at the same stage, fore-limb samples of different stages, hind-limb samples of different stages, and fore-limb samples compared to hind-limb samples at the same or the next stage.
Project description:To investigate into the evolutionary conversation of the single-cell transcriptome of human fetal limbs, especially the principles of forelimb and hindlimb specification and proximal-distal axis establishment, we collected the forelimbs and hindlimbs of mouse embryos matching human samples. We dissected the limbs to separate proximal, middle and distal parts and generated single-cell RNA-seq data of more than 70,000 cells. Combining this dataset with our human data, we are able to see highly conserved limb cell types and limb axis drivers. Several samples from already published studies GSM4227224, GSM4227225, GSM4227226, GSM4227227 (GSE142425) and GSM4498677, GSM4498678 (GSE149368) have been reused in data analyses and the corresponding processed data are also included with this submission.
Project description:Velo-cardio-facial syndrome/DiGeorge syndrome/22q11.2 deletion syndrome (22q11DS) patients have a submucous cleft palate, velo-pharyngeal insufficiency associated with hypernasal speech, facial muscle hypotonia and feeding difficulties. Inactivation of both alleles of mouse Tbx1, encoding a T-box transcription factor, deleted on 22q11.2, results in a cleft palate and a reduction or loss of branchiomeric muscles. To identify genes downstream of Tbx1 for myogenesis, gene profiling was performed on mandibular arches (MdPA1) from Tbx1+/+ and Tbx1-/- mouse embryos.
Project description:Velo-cardio-facial syndrome/DiGeorge syndrome/22q11.2 deletion syndrome (22q11DS) patients have a submucous cleft palate, velo-pharyngeal insufficiency associated with hypernasal speech, facial muscle hypotonia and feeding difficulties. Inactivation of both alleles of mouse Tbx1, encoding a T-box transcription factor, deleted on 22q11.2, results in a cleft palate and a reduction or loss of branchiomeric muscles. To identify genes downstream of Tbx1 for myogenesis, gene profiling was performed on mandibular arches (MdPA1) from Tbx1+/+ and Tbx1-/- mouse embryos. To obtain enough RNA for microarray hybridization experiments, dissected mandibular arches from three Tbx1+/+ and three Tbx1-/- E9.5 embryos were pooled according to genotype, with three microarrays performed in total per genotype. Affymetrix Mouse Gene ST 1.0 arrays (Affymetrix) were used. Hybridization, washing, staining and scanning were performed in the Genomics Core at Einstein (http://www.einstein.yu.edu/genetics/CoreFacilities.aspx?id=23934) according to the Affymetrix manual.
Project description:22q11 deletion syndrome (22q11DS) is mainly characterised by cardiovascular, craniofacial, thymic and parathyroid abnormalities. Haploinsufficiency of the transcription factor, TBX1 is considered to be a major underlying cause of these defects. Mice in which Tbx1 has been mutated phenocopy 22q11DS. In order to elucidate the transcriptional pathways regulated by Tbx1, the gene expression profile of Tbx1-lacZ positive cells isolated from E9.5 Df1/Tbx1lacZ embryos (Tbx1-null) were compared to cells isolated from Tbx1+/lacZ (Tbx1-heterozygous) embryos. This analysis has led to a better understanding of the pathways important in pharyngeal and heart development. Experiment design: 3 pools of cells (biological replicates) isolated from Df1/Tbx1lacZ embryos and Tbx1+/lacZ embryos were used for hybridisation onto 6 MOE430 v2 oligonucleotide array chips (Affymetrix), making 12 microarrays in total. Each pool of cells was isolated from at least 8 embryos.
Project description:Velo-cardio-facial syndrome/DiGeorge syndrome/22q11.2 deletion syndrome (22q11DS) patients have a submucous cleft palate, velo-pharyngeal insufficiency associated with hypernasal speech, facial muscle hypotonia and feeding difficulties. Inactivation of both alleles of mouse Tbx1, encoding a T-box transcription factor, deleted on 22q11.2, results in a cleft palate and a reduction or loss of branchiomeric muscles. To identify genes downstream of Tbx1 for myogenesis, gene profiling was performed on mandibular arches (MdPA1) from Tbx1+/+ and Tbx1-/- mouse embryos.
Project description:m6A regulates virtually every step in RNA metabolism. However, its toles in limb development remains largely unknown. To understand the roles, we created a limb bud-specific conditional knockout (cKO) mice and control heterozygous (cHet) mice of the Mettl14 gene, which encodes an essential subunit in the m6A methyltransferase complex METTL3/METTL14. We harvested limb buds from the mice on E12.5 and applied the proteins to quantitative mass spectrometry to understand how the depletion of Mettl14 affected the proteomes.
Project description:Detailed information about stage-specific changes in gene expression is crucial for understanding the gene regulatory networks underlying development and the various signal transduction pathways contributing to morphogenesis. Here, we describe the global gene expression dynamics during early murine limb development, when cartilage, tendons, muscle, joints, vasculature, and nerves are specified and the musculoskeletal system of the limbs is established. We used whole-genome microarrays to identify genes with differential expression at 5 stages of limb development (E9.5 to 13.5), during fore-limb and hind-limb patterning. We found that the onset of limb formation is characterized by an up-regulation of transcription factors, which is followed by a massive activation of genes during E10.5 and E11.5 which tampers off at later time points. Among 3520 genes identified as significantly up-regulated in the limb, we find ~30% to be novel, dramatically expanding the repertoire of candidate genes likely to function in the limb. Hierarchical and stage-specific clustering identified expression profiles that correlate with functional programs during limb development and are likely to provide new insights into specific tissue patterning processes. Here we provide for the first time, a comprehensve analysis of developmentally regulated genes during murine limb development, and provide some novel insights into the expression dynamics governing limb morphogenesis.
Project description:Velo-cardio-facial syndrome/DiGeorge syndrome/22q11.2 deletion syndrome (22q11DS) patients have a submucous cleft palate, velo-pharyngeal insufficiency associated with hypernasal speech, facial muscle hypotonia and feeding difficulties. Inactivation of both alleles of mouse Tbx1, encoding a T-box transcription factor, deleted on 22q11.2, results in a cleft palate and a reduction or loss of branchiomeric muscles. To identify genes downstream of Tbx1 for myogenesis, gene profiling was performed on mandibular arches (MdPA1) from Tbx1+/+ and Tbx1-/- mouse embryos. To obtain enough RNA for microarray hybridization experiments, dissected mandibular arches from three Tbx1+/+ and three Tbx1-/- E10.5 embryos were pooled according to genotype, with three microarrays performed in total per genotype. The tissue was homogenized in Buffer RLT (QIAGEN). Total RNA was isolated with the RNeasy Micro Kit according to the manufacturer’s protocol. Quality and quantity of total RNA was determined using an Agilent 2100 Bioanalyzer (Agilent) and an ND-1000 Spectrophotometer (NanoDrop), respectively. Biotinylated single-stranded cDNA targets were amplified from 100 nanograms (ng) starting total RNA using the Ovation RNA Amplification System V2 and FL- Ovation cDNA Biotin Module V2 (NuGEN). A total of 3.75 ?g of cDNA from the last step was hybridized to the GeneChip Test3 array (Affymetrix) to test the quality of the labeled target. Nucleic acid samples that passed quality control were then hybridized to the GeneChip Mouse Genome 430 2.0 Arrays (Affymetrix). Hybridization, washing, staining and scanning were performed in the Genomics Core at Einstein (http://www.einstein.yu.edu/genetics/CoreFacilities.aspx?id=23934) according to the Affymetrix manual.