Project description:BACKGROUND: Orofacial development is a multifaceted process involving precise, spatio-temporal expression of a panoply of genes. MicroRNAs (miRNAs) constitute the largest family of noncoding RNAs involved in gene silencing, and represent critical regulators of cell and tissue differentiation. MicroRNA gene expression profiling is an effective means of acquiring novel and valuable information regarding the expression and regulation of genes, under the control of miRNA, involved in mammalian orofacial development. RESULTS: To identify differentially expressed miRNAs during mammalian orofacial ontogenesis, miRNA expression profiles from gestation day (GD) -12, -13 and -14 murine orofacial tissue were compared utilizing miRXplore™ microarrays from Miltenyi Biotech GmbH. TaqManTM quantitative Real-Time PCR was utilized for validation of gene expression changes. Cluster analysis of the microarray data was conducted with the clValid R package and the UPGMA (hierarchical) clustering method. Functional relationships between selected miRNAs were investigated using Ingenuity Pathway Analysis. Expression of over 26% of the approximately 588 murine miRNA genes examined was detected in murine orofacial tissues from GD 12, 13 and 14. Among these expressed genes several clusters were seen to be developmentally regulated. Differential expression of genes encoding miRNAs within such clusters were shown to target genes encoding proteins involved in cell proliferation, cell adhesion, differentiation, apoptosis and epithelial-mesenchymal transformation, all processes critical for normal orofacial development. Functional relationships between miRNAs differentially expressed were investigated using Ingenuity Pathway Analysis (IPA; Ingenuity Systems). CONCLUSIONS: Using miRNA microarray technology, unique gene expression signatures of hundreds of miRNAs in embryonic orofacial tissue were defined. Gene targeting and functional analysis revealed that the expression of numerous protein-encoding genes, crucial to normal orofacial ontogeny, may be regulated by specific miRNAs. Time-course experiment (Developmental Stages), ICR mice embryos on gestational days (GD) 12, 13 and 14. Biological replicates: For each day of gestation, 3 independent pools of 15 to 20 staged embryos were used to procure embryonic orofacial tissues for preparation of 3 distinct pools of RNA that were independently processed and applied to individual miRXplore™ microRNA Microarray chips (Miltenyi Biotec GmbH). Technology: 2-color spotted cDNA, Hy5 (experimental sample) vs. Hy3 (control - miRXplore Universal Reference).
Project description:BACKGROUND: Orofacial development is a multifaceted process involving precise, spatio-temporal expression of a panoply of genes. MicroRNAs (miRNAs) constitute the largest family of noncoding RNAs involved in gene silencing, and represent critical regulators of cell and tissue differentiation. MicroRNA gene expression profiling is an effective means of acquiring novel and valuable information regarding the expression and regulation of genes, under the control of miRNA, involved in mammalian orofacial development. RESULTS: To identify differentially expressed miRNAs during mammalian orofacial ontogenesis, miRNA expression profiles from gestation day (GD) -12, -13 and -14 murine orofacial tissue were compared utilizing miRXplore™ microarrays from Miltenyi Biotech GmbH. TaqManTM quantitative Real-Time PCR was utilized for validation of gene expression changes. Cluster analysis of the microarray data was conducted with the clValid R package and the UPGMA (hierarchical) clustering method. Functional relationships between selected miRNAs were investigated using Ingenuity Pathway Analysis. Expression of over 26% of the approximately 588 murine miRNA genes examined was detected in murine orofacial tissues from GD 12, 13 and 14. Among these expressed genes several clusters were seen to be developmentally regulated. Differential expression of genes encoding miRNAs within such clusters were shown to target genes encoding proteins involved in cell proliferation, cell adhesion, differentiation, apoptosis and epithelial-mesenchymal transformation, all processes critical for normal orofacial development. Functional relationships between miRNAs differentially expressed were investigated using Ingenuity Pathway Analysis (IPA; Ingenuity Systems). CONCLUSIONS: Using miRNA microarray technology, unique gene expression signatures of hundreds of miRNAs in embryonic orofacial tissue were defined. Gene targeting and functional analysis revealed that the expression of numerous protein-encoding genes, crucial to normal orofacial ontogeny, may be regulated by specific miRNAs.
Project description:C57BL/6 mouse fetusus were subjected to transuterine fetal tracheal occlusion at gestational day 16.5 with collection of lung tissue at gestational day 18.5.
Project description:Genetic studies have revealed an essential role for cytosine DNA methylation in gene regulation. However, its spatiotemporal distribution in the developing embryo remains obscure. Here, we profiled the DNA methylation landscape of 12 mouse tissues/organs at 8 developmental stages spanning from early embryo to birth. In-depth analysis of such spatiotemporal epigenome maps uncovered widespread regulatory DNA element dynamics during embryogenesis. We systematically delineated methylation variants that likely drive gene transcription, whose human counterparts are enriched for genetic risk factors of human diseases. Strikingly, these predicted regulatory elements predominantly lose CG methylation during fetal development, whereas the trend is reversed after birth. Key transcription factors, essential for early tissue/organ development, accumulate non-CG methylation within their gene bodies, coinciding with transcriptional repression during late stage fetal development. These spatiotemporal epigenomic datasets provide a valuable resource for studies of gene regulation during mammalian tissue/organ progression and the possible origins of human developmental diseases.