Project description:Foxc1 and Foxc2 are highly expressed in adult podocytes. To bypass embryonic lethality of Foxc1 and Foxc2 KO, mice ubiquitously expressing inducible-Cre (ROSA26-CreERT2) were mated with floxed-Foxc1 and floxed-Foxc2 mice. We used microarrays to detail effects of deletions of Foxc1 and Foxc2 on podocyte gene expression profiles in adult podocyte in vivo and in vitro.
Project description:Endochondral ossification forms and grows the majority of the mammalian skeleton and is tightly controlled through gene regulatory networks. The forkhead box transcription factors Foxc1 and Foxc2 have been demonstrated to regulate aspects of osteoblast function in the formation of the skeleton but their roles in chondrocytes to control endochondral ossification are less clear. We demonstrate that Foxc1 expression is directly regulated by SOX9 activity, one of the earliest transcription factors to specify the chondrocyte lineages. Moreover we demonstrate that elevelated expression of Foxc1 promotes chondrocyte differentiation in mouse embryonic stem cells and loss of Foxc1 function inhibits chondrogenesis in vitro. Using chondrocyte-targeted deletion of Foxc1 and Foxc2 in mice, we reveal a role for these factors in chondrocyte differentiation in vivo. Loss of both Foxc1 and Foxc2 caused a general skeletal dysplasia predominantly affecting the vertebral column. The long bones of the limb were smaller and mineralization was reduced and organization of the growth plate was disrupted. In particular, the stacked columnar organization of the proliferative chondrocyte layer was reduced in size and cell proliferation in growth plate chondrocytes was reduced. Differential gene expression analysis indicated disrupted expression patterns in chondrogenesis and ossification genes throughout the entire process of endochondral ossification in Col2-cre;Foxc1Δ/Δ;Foxc2Δ/Δ embryos. Our results suggest that Foxc1 and Foxc2 are required for correct chondrocyte differentiation and function. Loss of both genes results in disorganization of the growth plate, reduced chondrocyte proliferation and delays in chondrocyte hypertrophy that prevents correct ossification of the endochondral skeleton.
Project description:Purpose: Next-generation sequencing (NGS) was used to define the transcriptome of native mouse podocytes and non-podocytes glomerular cells as part of a project aiming to define the molecular fingerprint of mouse podocytes. Method: Glomeruli from 29 Gt(ROSA)26Sortm4(ACTB-tdTomato,-EGFP)Luo/J x hNPHS2Cre mice at the age of 10 weeks were purified and a single cell solution was prepared to seperate GFP-expressing (podocytes) and GFP-negative (non-podocytes glomerular cells) cells by FACS sorting. RNA was extracted and prepared for further analysis using directional, polyA+ library preparation. An Illumina HiSeq2500 was used for a paired-end sequencing of 100 cycles . Salmon and Sleuth were used for downstream analysis. Results: A total of 100 Million reads each from podocytes and non-podocytes glomerular cells could be used for further analysis.
Project description:Podocytes, highly differentiated glomerular epithelial cells, are essential for the maintenance of glomerular filtration barrier. Podocyte dysfunction in podocytes is a major determinant of proteinuric kidney disease. By RNA sequencing analysis in ADR-treated podocytes with or without MYDGF overexpression, we observed the significant changes of genes important in regulating cell cycle in podocytes with ADR treatment.
Project description:Intestinal ischemia induces mucosal damage while simultaneously activating intestinal stem cells (ISCs), which subsequently regenerate the damaged intestinal epithelium. However, whether angiocrine factors secreted from vascular endothelial cells (ECs) - blood and lymphatic ECs (BECs and LECs, respectively) – regulate ISC-mediated regeneration have yet to be elucidated. Here, we identify FOXC1 and FOXC2 as essential regulators of angiocrine signaling in regeneration of the small intestine after ischemia-reperfusion (I/R) injury. EC- and LEC-specific deletions of Foxc1, Foxc2, or both in mice augment I/R-induced intestinal damage by causing defects in vascular regrowth, expression of the chemokine CXCL12 and the Wnt activator R-spondin 3 in BECs and LECs, respectively, and activation of Wnt signaling in ISCs. Treatment with CXCL12 and R-spondin 3 rescues the I/R-induced intestinal damage in EC- and LEC-Foxc mutant mice, respectively. This study provides evidence that FOXC1 and FOXC2 are required for intestinal regeneration by stimulating angiocrine CXCL12 and Wnt signaling.
Project description:The effect of miRNA delivery from glomerular endothelial cells (GEnCs) to podocytes in vitro was examined by miRNA epression in podocytes untreated and treated with extracellular vesicles from GEnCs under varied activation conditions.
Project description:The effect of miRNA delivery from glomerular endothelial cells (GEnCs) to podocytes in vitro was examined by mRNA epression in podocytes untreated and treated with extracellular vesicles from GEnCs under varied activation conditions.
Project description:We identified Fox1 and Foxc2 core transcription factors in kidney glomeruli. To investigate their transcriptional regulatory roles in glomeruli, we performed ChIPseq of Foxc1 and Foxc2 in adult mouse kidney glomeruli. The genome wide distribution of Foxc1/2 binding sites revealed they regulated the differentiation and mature state of adult podocyte to maintain kidney homeostatis.
Project description:In the context of human disease, the mechanisms whereby transcription factors reprogram gene expression in reparative responses to injury are not well understood. We have studied the mechanisms of transcriptional reprogramming in disease using murine kidney podocytes as a model for tissue injury. Podocytes are a crucial component of glomeruli, the filtration units of each nephron. Podocyte injury is the initial event in many processes that lead to End Stage Kidney Disease. FOXC2 is a transcription factor known to regulate gene expression in podocytes. FOXC2 and WT1 are both required for podocyte differentiation. Using murine models and human kidney organoids, we investigated FOXC2-mediated transcriptional reprogramming during the course of podocyte injury. Correlating FOXC2 and WT1 ChIP-seq analyses demonstrated that they co-bind many genes expressed in podocytes. Reprogramming the transcriptome involved highly dynamic changes in the binding of FOXC2 and WT1 to target genes during a reparative injury response.