Project description:The mouse embryonic yolk sac consists of a visceral yolk sac (VYS) and parietal yolk sac (PYS), and may function as a materno-fetal exchange system for nutrients, waste and gas, and physical protector for the embryo/fetus. The present study was undertaken to characterize gene expression of the VYS and PYS endodermal cells, and to identify their novel genetic markers from microarray data with RT-PCR and in situ hybridization analyses. As a result, Apoa4, Lrp2, Fxyd2, Slc34a3 and Entpd2 were selected as genetic markers of VYS epithelial cells. These markers were predominantly expressed in VYS epithelial cells, and may involve nutrient uptake and transport of various substances across the VYS membrane. Gkn2 and Pga5 were selected as markers for PYS cells. Gkn2 might be involved in the migration of PYS cells on Reichert’s membrane. Pga5 belongs to the aspartic proteinase family, and is known as ”pepsinogen F.” It may act on degradation of maternal proteins for the nutrient supply to the fetus. The present study also indicated that Mmp1a and Prl7b1 can be used as markers for placenta tissue. The markers reported may be useful for characterization of murine extraembryonic tissues, including yolk sacs and placenta, during development and in culture.
Project description:Purpose: Next-generation sequencing (NGS) has revolutionized systems-based analysis of cellular pathways. The goals of this study are to compare NGS-derived yolk sac transcriptome profiling (RNA-seq) of E16.5 Rsu1-/- mouse embryos to that of the wild-type controls Methods: Yolk sac mRNA profiles of yolk sac isolated from E16.5 wild-type (WT) and ras suppressor 1 (Rsu1−/−) emdbryos were generated by deep sequencing, in triplicate, using Illumina Hiseq 2500 platform. The sequence reads that passed quality filters were were mapped to human reference genome GRCh38 by HISAT2 v2.2.1 with default parameters. Results: Using an optimized data analysis workflow, we mapped about 40 million sequence reads per sample to the mouse genome and identified ___ transcripts in the yolk sacs of E16.5 WT and Rsu1−/− embryos with HISAT2 v2.2.1 workflow . Approximately __ % of the transcripts showed differential expression between the WT and Rsu1−/− yolk sac, with a fold change ≥2.0 and p value <0.05. Altered expression of 12 genes was confirmed with qRT–PCR, demonstrating the high degree of sensitivity of the RNA-seq method. Conclusions: Our study represents the first detailed analysis of E16.5 Rsu1-/- yolk sac transcriptomes, which would expedite genetic network analyses and permit the dissection of complex biologic functions of Rsu1 during late embryogenesis.
Project description:Primitive erythropoiesis in the mouse yolk sac is followed by definitive erythropoiesis resulting in adult erythrocytes. In comparison to definitive erythropoiesis little is known about the genes that control the embryonic erythroid program. The purpose of this study was to generate a profile of mouse embryonic yolk sac erythroid cells and identify novel regulatory genes differentially expressed in erythroid compared to non-erythroid (epithelial cells). The identification of these genes will contribute to a greater understanding of how the primitive erythroid program is controlled. This work will have clinical implications for treating sickle cell anemia and β-thalassemia. Activating genes in adult erythroid cells that increase embryonic or fetal globin gene expression may be a therapeutic approach to treat individuals with these disorders. Keywords: Comparison between mouse embryonic day 9.5 yolk sac microdissected primitive erythroid precursors and epithelial cells
Project description:Primitive erythropoiesis in the mouse yolk sac is followed by definitive erythropoiesis resulting in adult erythrocytes. In comparison to definitive erythropoiesis little is known about the genes that control the embryonic erythroid program. The purpose of this study was to generate a profile of mouse embryonic yolk sac erythroid cells and identify novel regulatory genes differentially expressed in erythroid compared to non-erythroid (epithelial cells). The identification of these genes will contribute to a greater understanding of how the primitive erythroid program is controlled. This work will have clinical implications for treating sickle cell anemia and β-thalassemia. Activating genes in adult erythroid cells that increase embryonic or fetal globin gene expression may be a therapeutic approach to treat individuals with these disorders. Experiment Overall Design: Embryonic day 9.5 (E9.5) yolk sacs were dissected from the embryos of timed-pregnant FVB/N mice. These tissues were frozen in OCT media and 8-micron frozen sections were obtained. Laser capture microdissection (LCM) was used to isolate primitive erythroid precursors and epithelial cells from these E9.5 yolk sac frozen sections using 2 to 4 yolk sacs from 2 different litters per biological replicate. Paired erythroid and epithelial samples were collected from the same microscope slides. Total RNA was isolated from 4 different pairs of erythroid and epithelial samples and hybridized to Affymetrix 430 A 2.0 microarrays.
Project description:GW182 (Tnrc6a) is a key component of RISC (miRNA-Induced Silencing Complex) that plays a critical role in miRNA-mediated gene silencing. Here, we show that GW182 is expressed in the yolk sac endoderm, and that gene-trap disruption of GW182 leads to growth arrest of yolk sac endoderm, impaired hematopoiesis and embryonic lethality. To investigate roles of GW182 in the yolk sac endoderm, we assessed changes in mRNA expression in the yolk sac of E9.5 GW182gt/gt embryos using microarrays (Affymetrix). Yolk sac of wild type littermates and GW182gt/gt embryos at E9.5 was collected for total RNA isolation using Trizol (Invitrogen). RNAs were purified according to the manufacturer’s protocol before subjected to Mouse Gene 1.0 ST Whole Genome Array (Affymetrix) for mRNA expression profiling. Experiments were performed in triplicate. Differentially expressed mRNAs were identified using a two-sample t-test (P<0.05 considered significant).
Project description:Investigating the blood, immune and stromal cells present in a human fetal embryo in a world first single cell transcriptomic atlas. The embryo was dissected into 12 coronal sections, yolk sac, and yolk sac stalk. Live single cells sorted, with cell suspension then undergoing 10x chromium 5 prime scRNA-seq. This accession contains the yolk sac and yolk sac stalk data from this embryo. A matched accession contains the coronal section data. Lane "WS_wEMB12142156" (from yolk sac) was excluded from downstream analysis due to low fraction reads in cells post-CellRanger QC. Termination procedure for this embryo was medical. The F158_[features...barcodes...matrix].[tsv...mtx].gz files attached to this accession represent raw count data from all the 10x lanes in this accession combined, and as output from CellRanger filtered matrices (CellRanger version 6.0.1 using human reference genome GRCh38-2020-A). One set of count matrices relates to the yolk sac data, and one set of count matrices relates to the yolk sac stalk data.
Project description:GW182 (Tnrc6a) is a key component of RISC (miRNA-Induced Silencing Complex) that plays a critical role in miRNA-mediated gene silencing. Here, we show that GW182 is expressed in the yolk sac endoderm, and that gene-trap disruption of GW182 leads to growth arrest of yolk sac endoderm, impaired hematopoiesis and embryonic lethality. To investigate roles of GW182 in the yolk sac endoderm, we assessed changes in mRNA expression in the yolk sac of E9.5 GW182gt/gt embryos using microarrays (Affymetrix).
Project description:This study aimed at exploring the physiological function of mammalian HYPB by means of knockout mouse model. Homogenous disruption of mouse Hypb gene leads to embryonic lethality at E10.5-E11.5. Severe vascular defects were observed in the Hypb-/- embryos, yolk sac and placenta.In the mutant embryo and yolk sac, disorganized and abnormally dilated capillaries cannot be remodeled into large blood vessels or intricate networks. Thus, our results suggest that the mammalian HYPB HMT plays an important role in embryonic vascularization. Keywords: knockout, mouse embryo development, angiogenesis, yolk sac, E9.0, E10.5