Comparative proteomic analysis of kidney distal convoluted tubule and cortical collecting duct cells following long-term hormonal stimulation
ABSTRACT: The distal convoluted tubule (DCT) and the cortical collecting ducts (CCD) are portions of renal tubule that are partly responsible for maintaining the systemic concentrations of potassium, sodium, calcium and magnesium. Despite being structurally similar, DCT and CCD cells have different transport capabilities due to a variety of different membrane-associated transport proteins. However, DCT and CCD cells appear to be modulated via the same hormones. The objective of this study was assess the differential response of DCT and CCD cells to long-term exposure to the hormones vasopressin or angiotensin II, both of which modulate DCT and CCD cells differently. Mass spectrometry based quantitative proteomics was used to profile the differential proteome between DCT and CCD.
Project description:Activation of the renal urine concentrating mechanism by vasopressin requires the coordinated regulation of multiple gene products including ion transporters, and water channels as well as regulatory proteins like protein kinases and phosphatases or enzymes involved in the energy-metabolism of the cells. We used microarray analysis of AVP-regulated gene products in a rat model of central diabetes insipidus (DI) to generate a comprehensive database documenting these changes. For microarray studies young (8 weeks) adult male Brattleboro rats were randomly divided into 2 groups (n = 3 per group) and treated for 3 days with either 1-desamino-8-D-Arg vasopressin (dDAVP; 5ng/h; Sigma Aldrich, Germany) or vehicle via osmotic minipump (ALZET minipump model 2001, Charles River, Sulzfeld, Germany). At the end of the treatment period animals were sacrificed and the kidneys removed. The outer medulla was isolated and used for cDNA generation and subsequent microarray analysis using [Rat230_2] Affymetrix Rat Genome 230 2.0 Array.
Project description:We sequenced mRNAs from glomeruli and 14 different rat renal tubule segments collected by hand microdissection. Collagenase-digested rat renal tubule segments were collected by hand microdissection. Poly(A)-mRNAs were captured from cell lysate and sequenced using paired-end protocol.
Project description:In order to characterize gene expression networks linked to AT1 angiotensin receptors in the kidney, we carried out genome-wide transcriptional analysis of RNA from kidneys of wild-type (WT) and AT1A receptor-deficient mice (KOs) at baseline and after 2 days of angiotensin II infusion (1 ug/kg/min), using Affymetrix GeneChip Mouse Genome 430 2.0 Arrays. At baseline, 405 genes were differentially expressed (>1.5X) between WT and KO kidneys. Of these, more than 80% were up-regulated in the KO group including genes involved in inflammation, oxidative stress, and cell proliferation. After 2 days of angiotensin II infusion in WT mice, expression of ~805 genes was altered (18% up-regulated, 82% repressed). Genes in metabolism and ion transport pathways were up-regulated while there was attenuated expression of protective genes against oxidative stress including glutathione synthetase and mitochondrial SOD2. Angiotensin II infusion has little effect on blood pressure in KOs. Nonetheless, expression of more than 250 genes was altered in kidneys from KO mice during angiotensin II infusion; 14% were up-regulated, while 86% were repressed including genes involved in immune responses, angiogenesis, and glutathione metabolism. Between WT and KO kidneys during angiotensin II infusion, 728 genes were differentially expressed; 10% were increased and 90% were decreased in the WT group. Differentially regulated pathways included those involved in ion transport, immune responses, metabolism, apoptosis, cell proliferation, and oxidative stress. This genome-wide assessment should facilitate identification of critical distal pathways linked to blood pressure regulation. To define gene expression patterns in kidney triggered by of activation AT1 receptors, we used genome-wide transcriptional analysis of RNA from kidneys of wild-type and AT1A receptor-deficient mice at baseline and after 2 days of angiotensin II infusion (1 ug/kg/min), using Affymetrix GeneChip Mouse Genome 430 2.0 Arrays. All of the experiments were conducted with male mice 2.5 months old and included 3 mice per experimental group. Synthesis of cRNA, hybridization and scanning of chips were conducted by Duke University microarray core facility (Duke University, Durham, NC).
Project description:The Ca2+/calmodulin-dependent kinase II is expressed in smooth muscle and believed to mediate intracellular calcium handling and calcium-dependent gene transcription. CaMKII is activated by Angiotensin-II. The multifunctional calcium/calmodulin-dependent kinase II (CaMKII) is activated by Angiotensin-II (Ang-II) in vascular smooth muscle cells (VSMC), but its impact on hypertension remains unknown. In our transgenic mice that express the inhibitor peptide CaMKIIN in smooth muscle (TG SM-CaMKIIN), the blood pressure response to chronic Ang-II infusion was significantly reduced as compared to littermate controls. Surprisingly, examination of blood pressure and heart rate under ganglionic blockade revealed a key role for VSMC CaMKII in efferent sympathetic outflow in response to Ang II hypertension. Consistently, the efferent splanchnic nerve activity and plasma phenylephrine concentrations were significantly lower in TG SM-CaMKIIN mice as compared to littermates. Moreover, the aortic depressor nerve activity was reset in hypertensive wild type animals, but not in TG SM-CaMKIIN mice, suggesting that changes in baroreceptor wall activity may be responsible for the blood pressure difference in Ang-II hypertension. The pulse wave velocity, a measure of vascular wall stiffness in vivo, was increased in aortas of hypertensive compared to normotensive WT animals. However, Ang-II infusion did not alter the pulse wave velocity in transgenic mice, suggesting that CaMKII in VSMC controls structural smooth muscle genes. Accordingly, analysis of gene expression changes in aortas from wild type and TG SM-CaMKIIN hypertensive mice demonstrated that CaMKII inhibition mainly altered the expression of muscle contractile proteins. In contrast, TG SM-CaMKIIN aortas were protected from the Ang-II induced upregulation of genes linked to proliferation, suggesting that CaMKII inhibition prevents the Ang-II-induced reprogramming of smooth muscle cell gene expression towards a proliferative phenotype. 5 WT C57Bl/6 and 5 mice that express the Ca2+/calmodulin-dependent kinase II peptide inhibitor CaMKIIN in smooth muscle only (TG SM-CaMKIIN) were infused with 1.25 ug/kg/min Angiotensin-II by osmotic minipump for 14 days. 5 WT and 5 transgenic mice infused with normal saline served as controls. The mice were sacrificed on day 14 and the thoracic aortas isolated. RNA was isolated and pooled for the following groups: WT (wild type), C (TG SM-CaMKIIN), WT-A (WT with Angiotensin-II), C-A (TG SM-CaMKIIN + Angiotensin-II)
Project description:The mouse mpkCCD cell line is a continuous cultured epithelial cell line with characteristics of renal collecting duct principal cells. This line is widely used to study epithelial transport and its regulation. To provide a data resource useful for experimental design and interpretation in studies using mpkCCD cells, we have carried out 'deep' proteomic profiling of these cells using three levels of fractionation (differential centrifugation, SDS-PAGE, HPLC) followed by tandem mass spectrometry to identify and quantify proteins. The use of multiple levels of fractionation increases the ability to detect low abundance proteins. As a result, we identified 6766 proteins in mpkCCD cells at a high level of stringency. These proteins are expressed over 7 orders of magnitude of protein abundance. The data are provided to users as a public data base at https://helixweb.nih.gov/ESBL/Database/mpkFractions/. The MS data were mapped back to gel slices to generate 'virtual western blots' for each protein. For most of the 6766 proteins, the apparent molecular weight from SDS-PAGE agreed closely with the calculated molecular weight. However, a substantial fraction (>15%) of proteins were found to run aberrantly, either with much higher or much lower than predicted. These proteins were analyzed to identify mechanisms responsible for altered mobility on SDS-PAGE (high or low isoelectric point, high or low hydrophobicity, physiological cleavage, residence in the lysosome, post-translational modifications and expression of alternative isoforms due to alternative exon usage). Additionally, this analysis identified a previously unrecognized isoform of aquaporin-2 with apparent molecular weight <20 kD.
Project description:To assess differential gene expression by APOL1 renal-risk (2 risk alleles) vs. non-risk (G0G0) genotypes in primary proximal tubule cells (PTCs), global gene expression (mRNA) levels were examined on Affymetrix HTA 2.0 arrays in primary PTCs cultured from non-diseased kidney in African Americans without CKD who underwent nephrectomy for localized renal cell carcinoma. To detect differentially expressed gene profiles attributable to APOL1 renal-risk genotypes, African American primary proximal tubule cells with two APOL1 renal-risk alleles (N=5) and lacking renal-risk alleles (N=25) were included in comparisons of global gene expression.
Project description:Angiotensin II (Ang II) mediated signaling plays a key role in the development of hypertension associated target organ damages. However, the gene expression changes regulated by Ang II in the early stage of acute cerebral, cardiac, renal, vascular injury remain unclear. we investigated Ang II–mediated gene expression alteration associated with the development of early cerebral, cardiac, renal, vascular injury by microarray assay in a mouse model. All mice were euthanized by an overdose of pentobarbital on days 1, 3 and 7 of Angiotensin II treatment. Total RNA was isolated with TRIzol (Invitrogen) from brains, hearts, kidneys and vessels (n=1-3 per group) at each time point according to manufacturer’s instructions. Gene expression profiling was performed using Affymetrix GeneChip mouse Genome 430 2.0 array according to the manufacturer’s instructions (Affymetrix, Inc., Santa Clara, CA). On the GeneChip Mouse Genome 430 2.0 Array, over 45,000 probe sets analyze the expression level of over 39,000 transcripts and variants from over 34,000 well characterized mouse genes.
Project description:Analysis of HeLa cells at 24 hours after transfection with wild type miR-1, miR-124, miR-181 versus control transfected HeLa cells. Results were compared to protein down-regulation at 48 hours measured by SILAC-MS. Analysis of HeLa cells at 24 hours after transfection with wild type miR-1, miR-124, miR-181 versus control transfected HeLa cells. Results were compared to protein down-regulation at 48 hours measured by SILAC-MS.
Project description:Background: Gq-coupled G protein-coupled receptors (GPCR) mediate the actions of a variety of messengers that are key regulators of cardiovascular function. Enhanced Gaq-mediated signaling plays an important role in cardiac hypertrophy and in the transition to heart failure. We have recently described that Gaq acts as an adaptor protein that facilitates PKCz-mediated activation of ERK5 in epithelial cells. Since the ERK5 cascade is known to be involved in cardiac hypertrophy, we have investigated the potential relevance of this pathway in Gq-dependent signaling in cardiac cells. Methodology/Principal Findings: We have explored the mechanisms involved in Gq-coupled GPCR-mediated stimulation of the ERK5 pathway and its functional consequences in cardiac hypertrophy using both cultured cardiac cells and an animal model of angiotensin- dependent induction of cardiac hypertrophy in wild-type and PKCz knockout mice. We find that PKCζ is required for the activation of the ERK5 pathway by Gq-coupled GPCR in cardiomyocytes and in cardiac fibroblasts. Stimulation of ERK5 by angiotensin II is blocked upon pharmacological inhibition or siRNA-mediated silencing of PKCz in primary cultures of cardiac cells and in cardiomyocytes isolated from PKCz-deficient mice. Moreover, these mice do not develop cardiac hypertrophy upon chronic challenge with angiotensin II, as assessed by morphological, biomarker, electrocardiographic and global gene expression pattern analysis. Conclusion/Significance: Our data put forward that PKCζ is essential for Gq- dependent ERK5 activation in cardiac cells and indicate a key cardiac physiological role for this recently described Gaq/PKCz/MEK5 signaling axis. Littermate wild-type and PKCz -/- male mice (32 weeks of age) were subjected to continuous infusion of angiotensin II (or PBS as a control) for 14 days, a well established model for the induction of cardiac hypertrohy
Project description:To annotate the regulatory elements in the renal tubule epithelial cells, we profiled 6 histone ChIP-seq in the human kidney epithelical cells (HKC8). We pulled down the DNA with specific antibodies of interests against histone tail modifications in the human rebal tubule epithelial cells. The result can be interpretated with ChromHMM for different states.