Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Stromal Fat4 acts non-autonomously with Dachsous1/2 to restrict the nephron progenitor pool

ABSTRACT: 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.

ORGANISM(S): Mus musculus

PROVIDER: GSE70452 | GEO | 2015/08/01

SECONDARY ACCESSION(S): PRJNA288710

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Shared Molecules

Only show the datasets with similarity scores above: 0.5

Threshold

0.5

Similar Datasets

Stromal Fat4 acts non-autonomously with Dachsous1/2 to restrict the nephron progenitor pool

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.

2015-08-01 | E-GEOD-70452 | biostudies-arrayexpress

Chromatin remodelers interact with Eya1 and Six2 to control nephron progenitor cell self-renewal maintenance

Project description:Eya1 interacts with Six1/2 to induce nephron fate and promote nephron progenitor self-renewal. Haploinsufficiency for these genes in humans causes kidney agenesis or hypoplasia. However, how the Eya1-centered network operates remains elusive. Here we identify Eya1's interacting factors via mass-spectrometry and show that Eya1 and Six2 interact with Brg1-based SWI/SNF chromatin-remodeling complex in the kidney. Depletion of Brg1 results in lack of metanephric mesenchyme and depletion of nephron progenitor cells, which is linked to loss of Eya1 expression. Transcriptional profiling reveals conspicuous downregulation of the proto-oncogene Pbx1 and the Dchs1/Fat4 signaling but premature upregulation of a large subset of genes for podocyte lineages and aberrant activation of oncogenic factors in Brg1-deficent cell. ChIP-seq identifies Brg1-occupancy to enhancers at Pbx1 to a distal enhancer of Eya1 that drives nephron progenitor-specific expression. We demonstrate Six2-dependent Brg1 enrichment to the proximal-promoter of Mycn and two distal enhancers of Pbx1, all of which govern nephron progenitor-specific expression in response to binding to Six2. Together, our results suggest a possible mechanism through which the functional specificity of Brg1-BAFs and Eya1-Six2 in cell cycle regulation and self-renewal of the nephron progenitors may be in part achieved.

2021-10-01 | GSE185050 | GEO

Haploinsufficiency for SIX2 increases nephron progenitor proliferation leading to elevated branching and nephron number

Project description:The regulation of final nephron number in the kidney is poorly understood. However, cessation of nephron formation occurs when the self-renewing nephron progenitor population commits to differentiation. Transcription factors within this progenitor population, such as SIX2, are assumed to control expression of genes promoting self-renewal such that homozygous Six2 deletion results in premature commitment and an early halt to kidney development. In contrast, Six2 heterozygotes were assumed to be unaffected. Using quantitative morphometry, we demonstrate here a paradoxical 18% increase in ureteric branching and final nephron number in Six2 heterozygotes, despite evidence for reduced levels of SIX2 protein and transcript. This is accompanied by a clear shift in nephron progenitor identity with a distinct subset of progenitor genes, including Cited1 and Meox1, downregulated, while others were unaffected. The net result was an increase in nephron progenitor proliferation, as assessed by elevated EDU labelling, an increase in MYC protein and transcriptional upregulation of MYC target genes. Reducing proliferation by introducing Six2 heterozygosity onto the Fgf20-/- background resulted in premature differentiation of the progenitor population. Overall, this data demonstrates a unique dose response of the nephron progenitors to the level of SIX2 protein in which the role of SIX2 in progenitor proliferation versus self-renewal is separable.

2017-12-31 | GSE103219 | GEO

p53 Enables Self Renewal of Nephron Progenitor Cells

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

2015-02-16 | E-GEOD-56253 | biostudies-arrayexpress

Genome-wide map of SIX2 and SIX1 binding in human embryonic kidney cortex

Project description:Nephron endowment is determined by the self-renewal and induction of a nephron progenitor pool established at the onset of kidney development. In the mouse, the related transcriptional regulators Six1 and Six2 play non-overlapping roles in nephron progenitors. Transient Six1 activity prefigures, and is essential for, active nephrogenesis. In contrast, Six2 maintains later progenitor self-renewal from the onset of nephrogenesis. We compared Six2’s regulatory actions in mouse and human nephron progenitors by chromatin immunoprecipitation followed by DNA sequencing (ChIP-seq). Surprisingly, SIX1 was identified as a SIX2 target unique to the human nephron progenitors. Further, RNA-seq and immunostaining revealed overlapping SIX1 and SIX2 progenitor activity in the 16 week human fetal kidney. Human SIX1 ChIP-seq revealed a similar set of targets to SIX2, and predicted both factors bind DNA through an identical recognition site. In contrast to the mouse where Six2 binds its own enhancers but doesn’t interact with DNA around Six1, both human SIX1 and SIX2 bind homologous SIX2 enhancers and putative enhancers positioned around SIX1. Transgenic analysis of a putative human SIX1 enhancer in the mouse revealed a transient, mouse-like, pre-nephrogenic, Six1 regulatory pattern. Together, these data demonstrate a divergence in SIX-factor regulation between mouse and human nephron progenitors. In the human, an auto/cross-regulatory loop drives continued SIX1 and SIX2 expression during active nephrogenesis. In contrast, the mouse establishes only an auto-regulatory Six2 loop. It is tempting to speculate that differential SIX-factor regulation may contribute to species differences in the duration of progenitor programs and nephron output.

2016-01-31 | GSE73865 | GEO

Transcriptional profiling of human and mouse nephron progenitor cells

2016-01-31 | GSE73866 | GEO

Genome-wide maps of Six2 and b-catenin in mesenchymal nephron progenitors

Project description:Self-renewing undifferentiated nephron progenitors express Six2, a transcription factor that is required for their maintenance as undifferentiated progenitors. Differentiation of nephron progenitors is triggered by Wnt/b-catenin signaling. In order to understand how Six2 and Wnt signaling counteract each other, we performed ChIP-seq of Six2 and b-catenin in mesenchymal nephron progenitor cells. Nephron progenitors were FACS-isolated from BAC transgenic Six2GFPcre-positive embryonic kidneys at E16.5. For Six2 ChIP, freshly FACS isolated Six2+ cells were used. For b-catenin ChIP, FACS isolated Six2+ cells were aggregated by centrifugation at 850g for 5min and incubated in 10%FBS/DMEM containing 4uM BIO for 24hrs.

2012-09-11 | E-GEOD-39837 | biostudies-arrayexpress

Genome-wide maps of Six2 and b-catenin in mesenchymal nephron progenitors

2012-09-11 | GSE39837 | GEO

Dissecting stages of human kidney development and Tumorigenesis with surface markers affords simple prospective Purification of nephron stem cells

Project description:When assembling a nephron during development a multipotent stem cell pool becomes restricted as differentiation ensues. A faulty differentiation arrest in this process leads to transformation and initiation of a Wilms' tumor. Mapping these transitions with respective surface markers affords accessibility to specific cell subpopulations. NCAM1 and CD133 have been previously suggested to mark human renal progenitor populations. Herein, using cell sorting, RNA sequencing, in vitro studies with serum-free media and in vivo xenotransplantation we demonstrate a sequential map that links human kidney development and tumorigenesis; In nephrogenesis, NCAM1+CD133- marks SIX2+ multipotent renal stem cells transiting to NCAM1+CD133+ differentiating segment-specific SIX2- epithelial progenitors and NCAM1-CD133+ differentiated nephron cells. In tumorigenesis, NCAM1+CD133- marks SIX2+ blastema that includes the ALDH1+ WT cancer stem/initiating cells, while NCAM1+CD133+ and NCAM1-CD133+ specifying early and late epithelial differentiation, are severely restricted in tumor initiation capacity and tumor self-renewal. Thus, negative selection for CD133 is required for defining NCAM1+ nephron stem cells in normal and malignant nephrogenesis. Human fetal kidney mRNA profiles of 3 cell populations (NCAM1+/CD133-, NCAM+/CD133+, NCAM-/CD133+) were generated by deep sequencing using Illumina HiSeq.

2016-04-01 | E-GEOD-78502 | biostudies-arrayexpress

p53 Enables Self Renewal of Nephron Progenitor Cells

2015-02-16 | GSE56253 | GEO