Single-cell RNA-seq of blastomeres from 2- to 32-cell stage mouse embryos
ABSTRACT: Transcriptomes were determined for all blastomeres of 28 embryos at the 2- (n=8), 4- (n=16) and 8-cell (n=4) stages, and for individual cells taken from 16- (n=6) and 32- (n=6) cell stage embryos. We also carefully monitored the 2- to 4-cell divisions noting whether the cleavage plane was meridional (M, along the Animal-Vegetal (AV) axis marked by the second attached polar body) or equatorial (E, bisecting the AV axis) and the order in which such divisions occurred. This resulted in four groups of 4-cell stage embryos: ME, EM, MM and EE, which were all collected 10 hours after the first 2- to 4-cell division.
Project description:In order to gain a global temporal picture of epiblast potency across implantation, we collected mouse embryos at E4.5, E4.75 and E5.0, and dissected the epiblast for deep-sequencing analysis.
Project description:The key aim of this experiment is to characterize the iPSC-Mφ population before and after pulmonary transplantation. For this purpose the following cell populations were compared: (i) transplanted iPSC-Mφ, (ii) Mφ obtained by in vitro differentiation of murine lineage-negative bone marrow cells (BM-Mφ), (iii) non-differentiated CD45.1 iPSC, (iv) murine alveolar Mφ (AMφ) isolated from the BALF of healthy control mice, and (v) iPSC-Mφ recovered from the transplanted animals two months after (PMT-Mφ).
Project description:Somitogenesis is the segmentation of the developing embryonic body axis into somites and is guided by oscillating genes, which create waves of expression that travel across the presomitic mesoderm (PSM) from posterior to anterior. Upon arrival of a wave at the PSM's anterior end, a new somite is formed. To identify genes that are expressed in a wave-like pattern we dissected the PSM of four different mouse embryos (pre-turned), separated the left and right sides, and divided each into five segments, from posterior to anterior (sampling sites 1 to 5). Each segment was used to construct libraries for high-throughput RNA-sequencing. For one embryo, we also sequenced two somites.
Project description:Clear cell renal cell carcinoma (ccRCC) initiated from the renal epithelium is the most prevalent histological type of adult kidney cancers. Dissecting intratumoral heterogeneity (ITH) of ccRCC has leveraged to extend our knowledge on how primary tumors harboring driver mutations evolve and spread to other sites. The cellular fractions within and across the primary (pRCC) and metastatic RCC (mRCC) are heterogeneous in both their genetic and biological features determining the variability in clinical aggressiveness and sensitivity to the therapy. To achieve sustainable therapeutic benefit with targeted agents in mRCC, the effective target should focus on signaling pathways that are related to driver mutations occurred early in the clonal evolution of the disease and thus should be common to primary tumor and metastatic sites. Considering that extensive genetic heterogeneity may result in drug response variability among patients and treatment resistance, the tailored strategies for metastatic RCC is urgently needed. Here, we analyze single-cell RNA-seq (scRNA-seq) data from a matched primary RCC (pRCC) and lung metastasis (mRCC) to dissect ITH at the highest resolution to date with the objective of discovering the better therapeutic regimen. In order to identify successful clonal propagation from patient to PDX samples and understand pathogenesis from primary to metastatic RCC, we performed whole-exome sequencing (WES, n=4) and matched aCGH (n=4) on bulk tumor samples. And we utilized single-cell RNA sequencing (scRNA-seq) to model and dissect functional heterogeneity acroass primary and metastatic RCC tumors. We checked whether of capturing live one cell, not more cells, in microfluidics by fluorescent microscopic observation. To construct RNA sequencing libraries, we performed further quality controls including adequate quantities and qualities of amplified transcriptomes respectively from single cells. Tumor cells from the parental mRCC (n=34), PDX-mRCC (n=36) and PDX-pRCC (n=46) were finally analyzed in this study after filtering out poor quality cells.
Project description:At variance with what is observed in mice, no distinct MAIT1 or MAIT17 subsets exist in human blood, as all MAIT cells express a variety of transcription factors such as Rorgt, Tbet, Eomes and Helios. However, they are also found in tissues in which they have specific effector functions. To determine these tissue programs, we analyzed the transcription pattern of MAIT cells as compared to mainstream memory (CD45RA-CD27+) CD4+ and CD8+ T cells from human blood and liver. The paired samples of blood and liver cells were obtained from patients operated for metastatic uveal melanoma (liver samples from a “healthy” liver fragment), and from the blood of healthy controls.
Project description:We explored how aging impacts transcriptional dynamics using single-cell RNA-sequencing to profile hundreds of CD4+ T cells from young and old mice from two divergent species. In young animals, immunological challenge drives a conserved transcriptomic switch from highly variable to tightly regulated gene expression, characterized by a strong up-regulation of a core activation program, coupled with a decrease in cell-to-cell variability. Aging significantly perturbed the activation of this core program, and increased expression heterogeneity across the population of cells in both species.
Project description:Induced pluripotent stem cell (iPSC)-derived dopamine neurons provide an opportunity to model Parkinson’s disease (PD) but neuronal cultures are confounded by cellular heterogeneity. By applying high-resolution single cell transcriptomic analyses to Parkinson’s iPSC-derived dopamine neurons carrying the GBA-N370S risk variant, we exploited intra-culture cellular heterogeneity to identify a progressive axis of gene expression variation leading to endoplasmic reticulum stress. Analysis of genes differentially-expressed (DE) along this axis identified the transcriptional repressor histone deacetylase 4 (HDAC4) as an upstream regulator of disease progression. HDAC4 was mislocalized to the nucleus in PD iPSC-derived dopamine neurons and repressed genes early in the disease axis, leading to late deficits in protein homeostasis. Treatment of iPSC-derived dopamine neurons with compounds known to modulate HDAC4 activity upregulated genes early in the DE axis, and corrected Parkinson’s-related cellular phenotypes. Our study demonstrates how single cell transcriptomics can exploit cellular heterogeneity to reveal disease mechanisms and identify therapeutic targets.
Project description:Despite intensive efforts, establishing porcine embryonic stem cells have been challenging. We recently derived mouse expanded potential stem cells (EPSCs) from individual blastomeres by inhibiting the activity of critical molecular pathways that predisposes lineage differentiation in the mouse preimplantation embryo. EPSCs had enriched molecular signatures of blastomeres and possessed the developmental potency to all embryonic and extraembryonic cell lineages. In this study, we report the derivation of porcine EPSC (pEPSC) lines either directly from preimplantation embryos or by reprogramming fetal fibroblasts. Under similar culture conditions, human ESCs and iPSCs can be converted, or somatic cells are directly reprogrammed, to EPSCs (hEPSCs) that display the molecular and functional attributes reminiscent of pEPSCs. Here, we performed Single-Cell RNA-seq experiments to characterise the transcriptional heterogeneity of the EPSCs.
Project description:The atrioventricular (AV) node is a recurrent source of potentially life-threatening arrhythmias. Nevertheless, limited data are available on its developmental control or molecular phenotype. We used a novel AV node-specific reporter mouse to gain insight into the gene programs determining the formation and phenotype of the AV node. In the transgenic reporter, green fluorescent protein (GFP) expression was driven by 160 kbp of Tbx3 and flanking sequences. GFP was selectively expressed in the AV canal of embryos, and in the AV node of adults, while all other Tbx3+ conduction system components, including the AV bundle, were devoid of GFP expression. Fluorescent AV nodal (Tbx3BAC-Egfp) and complementary working (NppaBAC336-Egfp) myocardial cell populations of E10.5 embryos and E17.5 fetuses were purified using fluorescence-activated cell sorting, and their expression profiles were assessed by microarray analysis. We constructed a comprehensive list of sodium, calcium, and potassium channels specific for the nodal or working myocard. Furthermore, the data revealed that the AV node and the working myocardium phenotypes diverge during development, but that the functional gene classes characteristic for both compartments are maintained. Interestingly, the AV node-specific gene repertoire consisted of multiple neurotrophic factors not yet appreciated to play a role in nodal development. These data present the first genome-wide transcription profiles of the AV node during development, providing valuable information concerning its molecular identity. Keywords: Tbx3, AV node, working myocardium, embryonic development, cardiac development, cardiac conduction system 24 samples: 6x working myocardium stage E10.5 (NppaBAC336-Egfp mice), 6x AV canal myocardium stage E10.5 (Tbx3BAC-Egfp mice), 6x working myocardium stage E17.5 (NppaBAC336-Egfp mice), 6x AV node myocardium stage E17.5 (Tbx3BAC-Egfp mice)
Project description:We performed expression analysis of 7-10 4-cell embryos resulting from sperm fragmented long RNA injections from control males or males exposed to early life stress into naive zygotes after female superovulation and natural mating with males.