Project description:In order to better understand the molecular basis for the heart defects seen in Zic3 null and epiblast CKO embryos, we investigated whether complete or epiblast-specific deletion of Zic3 would impact later embryonic heart development at the transcriptional level by whole genome expression microarray. The whole heart was carefully dissected out from 15.5 dpc Zic3 +/y, Zic3 flox/y, Zic3 flox/y; Sox2-cre, and Zic3 -/y embryos, total RNAs were extracted and purified using RNeasy Mini Kit (QIAGEN). Spectrophotometry (NanoDrop-1000 Spectrophotometer, Thermo Fisher Scientific) and microfluidic electrophoresis (Experion Automated Electrophoresis System, Bio-Rad Laboratories) were used for RNA quality control. In vitro transcription was performed using Illumina TotalPrep RNA Amplification Kit (Applied Biosystems/Ambion). cRNAs were hybridized onto Illumina MouseWG-6 v2.0 Expression BeadChips (Illumina) per manufacturer’s instructions.
Project description:In order to better understand the molecular basis for the heart defects seen in Zic3 null and epiblast CKO embryos, we investigated whether complete or epiblast-specific deletion of Zic3 would impact later embryonic heart development at the transcriptional level by whole genome expression microarray.
Project description:The heart, a vital organ which is first to develop, has adapted its size, structure and function in order to accommodate the circulatory demands for a broad range of animals. Although heart development is controlled by a relatively conserved network of transcriptional/chromatin regulators, how the human heart has evolved species-specific features to maintain adequate cardiac output and function remains to be defined. Here, we show through comparative epigenomic analysis the identification of enhancers and promoters that have gained activity in humans during cardiogenesis. These cis-regulatory elements (CREs) are associated with genes involved in heart development and function, and may account for species-specific differences between human and mouse hearts. Supporting these findings, genetic variants that are associated with human cardiac phenotypic/disease traits, particularly those differing between human and mouse, are enriched in human-gained CREs. During early stages of human cardiogenesis, these CREs are also gained within genomic loci of transcriptional regulators, potentially expanding their role in human heart development. In particular, we discovered that gained enhancers in the locus of the early human developmental regulator ZIC3 are selectively accessible within a subpopulation of mesoderm cells which exhibits cardiogenic potential, thus possibly extending the function of ZIC3 beyond its conserved left-right asymmetry role. Genetic deletion of these enhancers identified a human gained enhancer that was required for not only ZIC3 and early cardiac gene expression at the mesoderm stage but also cardiomyocyte differentiation. Overall, our results illuminate how human gained CREs may contribute to human-specific cardiac attributes, and provide insight into how transcriptional regulators may gain developmental roles through the evolutionary acquisition of enhancers.
Project description:Gene expression profiling was performed on CNS tissue from neonatal mice carrying the T9H translocation and maternal or paternal duplication of proximal Chromosomes 7 and 15. Our analysis revealed the presence of two novel paternally expressed intergenic transcripts at the PWS/AS locus. The transcripts were termed Pec2 and Pec3 for paternally expressed in the CNS.Our analysis also revealed imprinting of Magel2, Mkrn3, Ndn,Ube3a and Usp29, as well as Pec2 and Pec3 in embryonic brain, 15.5 dpc, and provided a survery of biallelically expressed genes on proximal Chromosomes 7 and 15 in embryonic and neonatal CNS. Experiment Overall Design: Eight samples were analyzed by microarray analysis using GeneChip 430B (no biological replicates). RNAs were from neonatal cortex and cerebellum, and from whole brain of 13.5 and 15.5 dpc embryos, purified from mice carrying either maternal or paternal duplication of proximal chromosomes 7 and 15.
Project description:LRRC10 is a heart-specific gene required for proper cardiac function. The effects of Lrrc10 deletion on gene expression in the embryonic mouse heart was investigated. Pregnant heterozygous Lrrc10 knockout mice (Lrrc10+/-) mated to male heterozygous knockouts (Lrrc10+/-), housed in 12 hour light:12 dark, ad lib feeding and drinking conditions, were sacrificed at embryonic day 15.5 (E15.5) and embryonic hearts were dissected for cardiac gene expression analysis. A two color, reference design experiment in which heart RNA from 2 Lrrc10 homozygous knockout embryos (Lrrc10-/-) were pooled and labeled with Cy5 and hybridized according to Agilent protocols against a reference pool of RNA madeup from respective tissue taken from littermate E15.5 wildtype (Lrrc10+/+) hearts and labeled with Cy3.
Project description:Here, we show through comparative epigenomic analysis the identification of enhancers and promoters that have gained activity in humans during cardiogenesis. These cis-regulatory elements (CREs) are associated with genes involved in heart development and function, and may account for species-specific differences between human and mouse hearts. Supporting these findings, genetic variants that are associated with human cardiac phenotypic/disease traits, particularly those differing between human and mouse, are enriched in human-gained CREs. During early stages of human cardiogenesis, these CREs are also gained within genomic loci of transcriptional regulators, potentially expanding their role in human heart development. In particular, we discovered that gained enhancers in the locus of the early human developmental regulator ZIC3 are selectively accessible within a subpopulation of mesoderm cells which exhibits cardiogenic potential, thus possibly extending the function of ZIC3 beyond its conserved left-right asymmetry role. Genetic deletion of these enhancers identified a human gained enhancer that was required for not only ZIC3 and early cardiac gene expression at the mesoderm stage but also cardiomyocyte differentiation. Overall, our results illuminate how human gained CREs may contribute to human-specific cardiac attributes, and provide insight into how transcriptional regulators may gain developmental roles through the evolutionary acquisition of enhancers.
Project description:An important facet of the oocyte to embryo transition in mammals is the rapid elimination of a subset of the maternal products that got accumulated during oogenesis. RNA studies support a view that the transition occurs quite rapidly. Whether this applies also for proteins remains to be determined beyond the very few cases known to date. We report that COPS3, the 3rd subunit of the COP9 signalosome complex, forms a large protein deposit in mouse oocytes (94th percentile of the riBAQ distribution). The one and only knock-out study had previously shown that Cops3 null (-/-) mouse embryos obtained from heterozygous intercrosses arrested after 5.5 dpc and were resorbed by 8.5 dpc mainly due to increased cell death in the epiblast (PMID: 12972600). However, more recent studies from our group ascribed Cops3 gene with a developmental role already at the 2-cell stage. Specifically, the sister blastomeres differ from each other in Cops3 mRNA levels and distribution, preceding the discordance of epiblast formation in derivative twin blastocysts, and implicating Cops3 in the molecular underpinnings of totipotency. This discrepancy between original knock-out result and recent observations can be resolved if we posit that the first requirement for Cops3 gene function was bridged by maternal protein that outlived the locus excision, consistent with the observation that Cops3 -/- blastocysts had the same immunostaining intensity as the +/- or +/+ counterparts in the original knock-out study. Thus, these contradicting observations support a hypothesis that 5.5 dpc may not have been the first time when the gene function was needed in development, but the second time. To test this hypothesis, pronuclear-stage mouse oocytes were subjected to an immunological method that directly targets the protein of interest by way of proteasomal degradation of the COPS3-antibody-TRIM21 complex. Briefly, pronuclear-stage mouse oocytes were microinjected with a mixture of the COPS3-specific purified monoclonal IgG antibody, mCherry-Trim21 mRNA and Oregon Green dextran beads (inert tracer). Injected oocytes were then allowed to develop and collected for lysis 24 hours later, when they reached the 2-cell stage but were not able to progress further. In addition to the COPS3, we targeted two additional proteins, OCT4 and TEAD4. The following seven experimental groups were examined by liquid chromatography-mass spectrometry (LC-MS/MS) using the pipeline described previously by Israel et al.: 1) non-manipulated 2-cell embryos; 2) 2-cell embryos from oocytes injected with Oregon Green dextran beads; 3) 2-cell embryos from oocytes injected with mCherry-Trim21 mRNA and Oregon Green; 4) 2-cell embryos from oocytes injected with mCherry-Trim21 mRNA, Oregon Green and anti-COPS3 (Abcam 79698); 5) 2-cell embryos from oocytes injected with anti-COPS3 (Abcam 79698) and Oregon Green; 6) 2-cell embryos from oocytes injected with mCherry-Trim21 mRNA, Oregon Green and anti-TEAD4 (Abcam 58310); 7) 2-cell embryos from oocytes injected with mCherry-Trim21 mRNA, Oregon Green and anti-OCT4 (Abcam 181557).
Project description:Transcriptional profiling of the preingression epiblast versus lateral epiblast, of preingression epiblast from control embryos treated with the DMSO carrier vehicle (0.5%) versus embryos treated with SU5402, U0126 or LY294002. Embryos were stages 5-6 at time of tissue isolation. The preingression epiblast (E2 region) is the region of epiblast just lateral to the primitive streak. Lateral epiblast is the E3 region. Two condition experiment. Samples for each condition isolated from at least 30 embryos.
Project description:Transcriptional profiling of the preingression epiblast versus lateral epiblast, of preingression epiblast from control embryos treated with the DMSO carrier vehicle (0.5%) versus embryos treated with SU5402, U0126 or LY294002. Embryos were stages 5-6 at time of tissue isolation. The preingression epiblast (E2 region) is the region of epiblast just lateral to the primitive streak. Lateral epiblast is the E3 region. Two condition experiment. Samples for each condition isolated from at least 30 embryos. The experiments used isolated preingression epiblast, which is defined as the region of epiblast adjacent to the primitive streak that will ingress through the primitive streak. Preingression epiblast was isolated by microdissection using tungsten needles from control embryos or embryos treated with SU5402, U0126 or LY294002.
Project description:Comparison of gene expression levels between matUPD12 and patUPD12 15.5 dpc whole embryo or placenta samples (maternal versus paternal uniparental disomy of Chr 12). Identification of highly differentially expressed transcripts. Keywords: genetic modification