Project description:Purpose: Transport processes in the renal collecting duct are responsible for precise regulation of blood pressure and body fluid composition. The collecting duct is composed of at least three cell types, type A intercalated cells (A-IC), type B intercalated cells (B-IC) and principal cells (PC). To identify the genes that are selectively expressed in each cell type, including cell-surface receptors, transcription factors, transporters and secreted proteins, we used cell surface markers necessary for isolation of each of the three cell types using fluorescence-activated cell sorting and carried out single-cell RNA-Seq to measure the mRNA species in each of these cell types. Methods: We enriched each of the three cell types using fluorescence-activated cell sorting. Subsequently, we carried out single-cell RNA-Seq of those cells using a microfluidic chip (Fluidigm C1 system). Single-cell cDNA libraries were constructed for paired-end sequencing and sequenced on Illumina HiSeq3000 platform. In addition, we also microdissected mouse CCDs and cTALs and carried out single-tubule RNA-Seq. Reads were mapped to mouse Ensembl Genome by STAR and transcript abundances were calculated in the units of transcripts per million (TPM) using RSEM (https://github.com/deweylab/RSEM). Single-cell RNA-Seq data anaysis were carried out using Seurat package in R. Results and conclusion: Single-cell cDNA libraries were constructed for paired-end sequencing and at least 10-million sequence reads per cell were mapped to the mouse genome (Ensembl, GRCm38.p5). On average, cells were sequenced to a depth of 3000 genes (TPM>1). Unsupervised clustering analysis revealed five different cell types, namely type A intercalated cells (n=87), type B intercalated cells (n=23), principal cells (74), proximal tubule cells (n=19), and non-epithelial cells (n=32). The identified patterns of gene expression among A-ICs, B-ICs and PCs provide a foundation for understanding physiological regulation and pathophysiology in the renal collecting duct.
Project description:Analysis of expression changes in renal collecting duct epithelial cells by adenoviral mediated Krüppel like transcription factor 5 (KLF5) overexpression. KLF5 is a key regulator of static and inflammatory stage in renal collecting duct epithelial cells. We thought these results provide insights into downstream genes of KLF5 in renal collecting duct epithelial cells.
Project description:Vasopressin is the major hormone that regulates renal water excretion. It does so by binding to a receptor in renal collecting duct cells, triggering signaling pathways that ultimately regulate the abundance, location, and activity of the water channel protein aquaporin 2. We took an advantage of quantitative large scale proteomic technologies and oligonucleotide microarrays to quantify steady state changes in protein and transcript abundances in response to vasopressin in a collecting duct cell line, mpkCCD clone 11 (Yu et al. PNAS 2009, 106:2441-2446). This cell line originally developed by Alan Vandewalle’s group recapitulates vasopressin-mediated AQP2 expression and phosphorylation as seen in native colleting duct cells.
Project description:Transcriptional profiling of new born mouse kidney collecting duct (CD) cells comparing the infuence of gestational high salt stress on gene expression remolding of BdkrB2 receptor knockout CD cells with that of BdkrB2 receptor wild type CD cells. The BdkrB2 receptor has been shown to be playing a role in renal vascular tone, kidney secretion and reabsorption function, normal kidney development, while impaired BdkrB2 receptor in kidney shown being associated with renal agenesis and renal dysplasia. Goal was to determine the effects of BdkrB2 receptor knockout together with gestational high salt stress on collecting duct gene expression pattern. Single color microarray experiment, BdkrB2 knockout new born mouse CD cells vs. BdkrB2 WT mosue CD cells with both on gestational high salt stress. Biological replicates: 3 BdkrB2 null replicates, 3 BdkrB2 WT replicates. Expression level of each sample was normalized to WT1 replicate.
Project description:Analysis of expression changes in renal collecting duct epithelial cells by adenoviral mediated Krüppel like transcription factor 5 (KLF5) overexpression. KLF5 is a key regulator of static and inflammatory stage in renal collecting duct epithelial cells. We thought these results provide insights into downstream genes of KLF5 in renal collecting duct epithelial cells. Total RNAs were isolated from adenovirally-mediated KLF5 over expressed cultured mIMCD-3 cells or control adenovirus infected mIMCD-3. We analyzed these two gene expression profiles after 24 hours after infection.
Project description:We would like to know the gene expression pattern in absence of transcription factor GATA2 in adult renal collecting duct We used Gata2 flox::Pax8-rtTA::Tet-Cre to make a doxycycline induced Gata2 renal tubule cell specific knockout mice We performed microarray analyses using DBA-lectin and magnetic beads purifed collecting duct cells from WT (n=3) or Gata2 CKO mice (n=3) at 4-weeks after doxycycline induction
Project description:Vasopressin is the major hormone that regulates renal water excretion. It does so by binding to a receptor in renal collecting duct cells, triggering signaling pathways that ultimately regulate the abundance, location, and activity of the water channel protein aquaporin 2. We took an advantage of quantitative large scale proteomic technologies and oligonucleotide microarrays to quantify steady state changes in protein and transcript abundances in response to vasopressin in a collecting duct cell line, mpkCCD clone 11 (Yu et al. PNAS 2009, 106:2441-2446). This cell line originally developed by Alan Vandewalle’s group recapitulates vasopressin-mediated AQP2 expression and phosphorylation as seen in native colleting duct cells. The mpkCCD cells were grown on membrane supports to permit polarization. Once transepithelial resistance reached 5kohm per centimeter square and higher, the cells were exposed to the vasopressin V2 receptor analog, dDAVP, at a physiological concentration, 0.1nM, for 5 days. Control experiments were done with cells exposed to vehicle alone. Total RNA was harvested and processed for transcript expression analysis using Affymetrix GeneChip Mouse Genome 430 2.0 Arrays. Each experimental treatment, vehicle and dDAVP, was repeated 3 times.
Project description:Phosphorylation of the aquaporin-2 (AQP2) water channel at four COOH-terminal serines plays a central role in the regulation of water permeability of the renal collecting duct. The level of phosphorylation at these sites is determined by a balance between phosphorylation by protein kinases and dephosphorylation by phosphatases. The phosphatases that dephosphorylate AQP2 have not been identified. Here, we use large-scale data integration techniques to identify serine-threonine phosphatases likely to interact with AQP2 in renal collecting duct principal cells. As a first step, we have created a comprehensive list of 38 S/T phosphatase catalytic subunits present in the mammalian genome. Then we used Bayes’ theorem to integrate available information from large-scale data sets from proteomic and transcriptomic studies in order to rank the known S/T phosphatases with regard to the likelihood that they interact with AQP2 in renal collecting duct cells. To broaden the analysis, we have generated new proteomic data (LC-MS/MS) identifying 4538 distinct proteins including 22 S/T phosphatases in cytoplasmic fractions from native inner medullary collecting duct cells from rats. The official gene symbols corresponding to the top-ranked phosphatases (common names in parentheses) were: Ppp1cb (PP1-beta), Ppm1g (PP2C), Ppp1ca (PP1-alpha), Ppp3ca (PP2-B or calcineurin), Ppp2ca (PP2A-alpha), Ppp1cc (PP1-gamma), Ppp2cb (PP2A-beta), Ppp6c (PP6C) and Ppp5c (PP5). This ranking correlates well with results of prior reductionist studies of ion and water channels in renal collecting duct cells.
Project description:Vasopressin/cAMP/protein kinase A (PKA) signaling phosphorylates AQP2 water channels in renal collecting ducts to reabsorb water from urine for the prevention of further water loss. Lipopolysaccharide-responsive and beige-like anchor protein (LRBA) mediates vasopressin-induced AQP2 phosphorylation; therefore LRBA is essential for urinary concentration. LRBA is identified as the PKA substrates in a mouse cortical collecting duct principal cell line (mpkCCDcl4) whose phosphorylation levels are nearly perfectly correlated with those of AQP2. Although mouse LRBA contains several consensus PKA phosphorylation sites, their phosphorylation status in response to vasopressin remain unknown. Post-translational modification analysis revealed that RRDS1607 and RRIS2189 were phosphorylated by vasopressin.
Project description:Purpose: PKA plays a crucial role in vasopressin signaling of renal collecting duct cells. To understand regulation of mRNA expression mediated by vasopressin/PKA signaling, mRNA expression was profiled by RNA-Seq in double knockout cells (both PKA catalytic genes) generated from mouse cortical collecting duct mpkCCD cell line versus control lines with intact PKA expression. Methods: PKA double knockout (dKO) cell lines were generated from mouse cortical collecting duct mpkCCDc11 cells by CRISPR/Cas-9 genome editing method. For mRNA profiling using RNA-Seq analysis, three biological replicates of control (not mutated in PKA two catalytic subunits) cell lines and PKA double knockout cell lines were used. The reads uniquely mapped on GENCODE mouse gene set were analyzed with HOMER (v4.8) and edgeR (v3.10.5). Results and conclusion: About 40-50 million sequence reads per sample were sucessfully mapped in the mouse genome (GENCODE, GPCm38.p5). Among total transcripts of the mouse genome, 10,190 transcripts (cutoff: Counts Per Million > 4 by edgeR) were considered as genes expressed in the cell lines. In differential expression analysis by standard edgeR analysis, 354 transcripts were differentially expressed between control cell lines and PKA dKO cell lines (FDR < 0.05). We also identified nine genes that were markedly decreased in PKA dKO cell lines (log2 PKA dKO/Control < -2, FDR < 0.05) including aquaporin-2 (Aqp2) and two genes that were markedly increased in PKA dKO cell lines (log2 PKA dKO/Control > 2, FDR < 0.05). These results suggest PKA signaling is important for regulation of expression of a very limited number of genes in vasopressin-responsive renal collecting duct cells.