Project description:Purpose: To use single-cell RNA-Seq analysis of nephron progenitors in order to determine transcrptional differences as nephron progenitors age. Methods: Using a combination of FACS sorting and a Fluidigm Single-cell auto-prep system, we generated high-throughput RNA-SEQ data of nephron progenitors during development Results: Single cells transcriptome profiling of nephron progenitors revealed progressive age-dependent changes with heterogeneity increasing in older populations. 96-single cell transcriptomes were determined from nephron progenitors of e14.5, e18.5 and P0 using Cited1GFP transgenic animals
Project description:Purpose: To use single-cell RNA-Seq analysis of nephron progenitors in order to determine transcrptional differences as nephron progenitors age. Methods: Using a combination of FACS sorting and a Fluidigm Single-cell auto-prep system, we generated high-throughput RNA-SEQ data of nephron progenitors during development Results: Single cells transcriptome profiling of nephron progenitors revealed progressive age-dependent changes with heterogeneity increasing in older populations.
Project description:Regulation of the balance between progenitor self-renewal and differentiation is critical to development. In the mammalian kidney, reciprocal signaling between three lineages (stromal, mesenchymal and ureteric) ensures correct nephron progenitor self-renewal and differentiation. Loss of either the atypical cadherin Fat4 or its ligand Dachsous1 (Dchs1) results in expansion of the mesenchymal nephron progenitor pool, called the condensing mesenchyme (CM). This has been proposed to be due to misregulation of the Hippo kinase pathway transcriptional co-activator YAP. Here, we use tissue-specific deletions to prove that Fat4 acts non-autonomously in the renal stroma to control nephron progenitors. We show that loss of Yap from the CM in a Fat4-null background does not reduce the expanded CM, indicating Fat4 regulates the CM independent of YAP. Analysis of Six2-/-;Fat4-/- double mutants demonstrates that excess progenitors in Fat4 mutants are dependent on Six2, a critical regulator of nephron progenitor self-renewal. Electron microscopy reveals that cell organization is disrupted in Fat4 mutants. Gene expression analysis demonstrates that the expression of Notch and FGF pathway components are altered in Fat4 mutants. Finally, we show that Dchs1, and its paralog Dchs2 function in a partially redundant fashion to regulate the number of nephron progenitors. Our data supports a model in which FAT4 in the stroma binds to DCHS1/2 in the CM to restrict progenitor self-renewal. A total of 3 Fat4-/- mutant embryos and 3 wildtype (Fat4+/+) control embryos were examined. Two kidneys from each embryo was used thereby yielding a total of 6 Fat4-/- mutant kidneys and 6 Fat4+/+ wildype kidneys. All kidneys examined were at E13.5.
Project description:Transcriptional profiling of FACS-sorted Six2-positive nephron progenitor cells from Six2CreEGFP mice without (WT) or with (MUT) homozygously floxed HDAC1 and HDAC2 alleles at the age of embryonic day 15.5. This experiment aimed to uncover the genome-wide alternation in gene expression resulting from the removal of HDAC1&2 in the nephron progenitor population and successive changes to the series of events in kidney development.
Project description:The goal of this study was to identify changes in gene expression within nephron progenitors and the whole embryonic kidney between Wnt11 mutants and wild type animals. Wnt11 mutant kidneys have disorganized nephron progenitor niches. Ultimately, nephron endowment is reduced by 50% in Wnt11 mutants. Gene expression changes are minimal between mutant and wild type samples, suggesting Wnt11 may act through non-canonical, non-transcritional mechanisms to regulate kidney development.
Project description:Regulation of the balance between progenitor self-renewal and differentiation is critical to development. In the mammalian kidney, reciprocal signaling between three lineages (stromal, mesenchymal and ureteric) ensures correct nephron progenitor self-renewal and differentiation. Loss of either the atypical cadherin Fat4 or its ligand Dachsous1 (Dchs1) results in expansion of the mesenchymal nephron progenitor pool, called the condensing mesenchyme (CM). This has been proposed to be due to misregulation of the Hippo kinase pathway transcriptional co-activator YAP. Here, we use tissue-specific deletions to prove that Fat4 acts non-autonomously in the renal stroma to control nephron progenitors. We show that loss of Yap from the CM in a Fat4-null background does not reduce the expanded CM, indicating Fat4 regulates the CM independent of YAP. Analysis of Six2-/-;Fat4-/- double mutants demonstrates that excess progenitors in Fat4 mutants are dependent on Six2, a critical regulator of nephron progenitor self-renewal. Electron microscopy reveals that cell organization is disrupted in Fat4 mutants. Gene expression analysis demonstrates that the expression of Notch and FGF pathway components are altered in Fat4 mutants. Finally, we show that Dchs1, and its paralog Dchs2 function in a partially redundant fashion to regulate the number of nephron progenitors. Our data supports a model in which FAT4 in the stroma binds to DCHS1/2 in the CM to restrict progenitor self-renewal.
Project description:p53 limits the self-renewing ability of a variety of stem cells. Here, contrary to its classical role in restraining cell proliferation, we demonstrate a divergent function of p53 in maintenance of self-renewal of the nephron progenitor population in the embryonic mouse kidney. p53-null nephron progenitor cells (NPC) exhibit progressive loss of the self-renewing progenitor niche in the cap mesenchyme, identified by Cited1 and Six2 expression, and loss of cap integrity. Nephron endowment is regulated by NPC availability and their differentiation to nephrons. Quantitatively, the Six2p53-/- cap has 30% fewer Six2GFP+ cells. While the apoptotic index is unchanged the proliferation index is significantly lower, in accordance with cell cycle analysis data showing less mutant Six2p53-/-;GFP+ cells in S and G2/M phases in comparison to Six2p53+/+;GFP+ cells. The mutant kidneys also show nephron deficit and decreased Fgf8 expression. To investigate the underlying changes in gene expression in the cap mesenchyme that contribute to the Six2p53-/- phenotype, we utilized RNA-Seq for transcriptome comparison. Top biological processes affected by p53 loss are development and morphogenesis, cell adhesion/migration, cell survival and metabolism. Cells from the mutant CM showed increased cellular ROS levels as well as deregulated expression of energy metabolism and mitochondrial genes suggesting metabolic dysfunction. Adhesion defects are visualized by decreased immunostaining of adhesion marker NCAM, and may possibly contribute to the differentiation defect as well. Altogether our data suggest a novel role for p53 in enabling self-renewal of the NPC and preservation of the progenitor niche, and thus regulating nephron endowment. mRNA profiles of wild-type (WT) and conditional p53 knockout (KO) of Six2+ mouse nephron progenitor cells (NPC) at embryonic day 15.5
Project description:Analysis of induced nephron progenitor cells from female/male urine cells (iNPC-F/INPC-M) by defined transcription factors vs. ESC derived nephron progenitor cell (ESC-NPC_H9/ESC-NPC_BG01) and female/male urine cells (UC-F/UC-M). Results provide insight into molecular similarities between induced nephron progenitor cells and human ESC derived nephron progenitor cell
Project description:During development, nephron progenitor forming one million nephrons, a functional unit in the kidney. However, nephron progenitor ceases before birth in human when they terminally differentiated to the nephron. Our lab established the method for induction of nephron progenitors from mouse Embryonic Stem (ES) cells and/or human induced Pluripotent Stem Cells (iPSCs) (Taguchi et al., Cell Stem Cell. 2014, 2017). For application of induced nephron progenitors to regenerative medicine, a large number of cells are required such as disease modeling and drug screening. To selectively propagate human iPS-derived nephron progenitors in vitro in an undifferentiated state, we developed SIX2-GFP iPS line and optimized culture condition of induced nephron progenitors by modifying our previously developed condition (Tanigawa et al., Cell Rep. 2016). To understand how whole gene expression profiles of human iPS-derived nephron progenitor cells are changed during culture, we isolated nephron progenitor cells by FACS and cultured in our defined culture condition. Purified RNAs from cultured cells at day 7 or un-cultured nephron progenitor cells were analyzed by RNA-seq.