Project description:To compare the tumor susceptibility between the hypertensive Dahl salt-sensitive rats (S) rat and S.LEW(10)x12x2x3x5 (S.LEW) congenic strain, one of the S.LEW congenic strains our laboratory previously constructed on rat chromosome 10 [Hypertension. 2007 Nov;50(5):891-8], Azoxymethane (AOM)-induced colon tumorigenesis in rats was assessed. At six weeks of age, both S and S.LEW congenic rats received intraperitoneal (IP) injection of AOM in sterial saline at a dose of 15mg/kg body weight once a week for two consecutive weeks. At 30 weeks of age, all the rats were euthanized through carbon dioxide inhalation. The colon tissue was harvested, dissected longitudinally, and washed with saline. The number and size of the colon tumors were recorded. We found that the total number of colon tumors was significantly higher in the S.LEW congenic strain compared with the S rat. To further study the genetic and molecular mechanisms causing the higher tumor susceptibility in the S.LEW congenic strain, we have employed the whole genome microarray expression profiling to identify genes and signaling pathways that are differential between the S and S.LEW congenic strain.
Project description:To get more insight in cause and consequences of proteinuria, we studied glomerular gene expression patterns before and after the onset of increased urinary albumin excretion in a proteinuric rat strain. Spontaneously proteinuric Dahl salt-sensitive rats (Dahl SS) were compared to non-proteinuric, spontaneously hypertensive rats (SHR). In Dahl SS, UAE significantly increased starting from week 5 of age. Glomerular RNA profiles of 4- and 6 week-old rats were studied by Affymetrix microarrays. Keywords: Time course analysis
Project description:Evidence from multiple linkage and genome-wide association studies suggest that human chromosome 2 (HSA2) contains alleles that influence blood pressure (BP). Homologous to a large segment of HSA2 is rat chromosome 9 (RNO9), to which a BP quantitative trait locus (QTL) was previously mapped. The objective of the current study was to further resolve this BP QTL. Eleven congenic strains with introgressed segments spanning <81.8kb to <1.33Mb were developed by introgressing genomic segments of RNO9 from the Dahl salt-resistant (R) rat onto the genome of the Dahl salt-sensitive (S) rat and tested for BP. The congenic strain with the shortest introgressed segment spanning <81.8kb significantly lowered BP of the hypertensive S rat by 25 mm Hg and significantly increased its mean survival by 45 days. In contrast, two other congenic strains had increased BP compared with the S. We focused on the <81.8kb congenic strain which represents the shortest genomic segment to which a BP QTL has been definitively mapped to date in any species. Sequencing of this entire region in both S and R rats detected 563 variants. The region did not contain any known or predicted rat protein coding genes. Further, a whole genome renal transcriptome analysis between S and the <81.8kb S.R congenic strain revealed alterations in several critical genes implicated in renal homeostasis. Taken together, our results provide the basis for future studies to examine the relationship between the candidate variants within the QTL region and the renal differentially expressed genes as potential causal mechanisms for BP regulation.
Project description:We used Affymetrix GeneChips to expression profile kidneys from Dahl salt-senstive hypertensive inbred strain and less hypertensive S.LEW(D1MCO4x1x3Bx1) congenic strain to identify genes downstream of Adamts16 (the function of Adamts16 has yet to be fully delineated). The S.LEW(D1MCO4x1x3Bx1) congenic animal is an S rat containing the LEWIS allele for Adamts16 instead of the S allele. It is hypothesized that allelic differences in Adamts16 in inbred rats is responsible for blood pressure variance. We further hypothesize that gene expression differences in the kidneys of S.LEW(D1MCO4x1x3Bx1) versus S result from sequence differences between the S and LEWIS alleles of Adamts16. Lastly, the downstream genes differentially regulated by the Adamts16 alleles may provide insight pertaining to the mechanism of blood pressure differences. Gene expression differences resulting from these kidney comparisons will be compared to the gene expression profiling experiments comparing siRNA-mediated knockdown of Adamts16 in NRK-52E kidney cells versus scrambled siRNA control. Experiment Overall Design: Kidney RNA from 3 Dahl salt-sensitive rats was extracted for target preparation and hybridization onto Affymetrix GeneChips. We also isolated kidney RNA from 3 S.LEW(D1MCO4x1x3Bx1) congenic rats for target preparation and hybridization onto Affymetrix GeneChips.
Project description:We used Affymetrix GeneChips to expression profile rat kidney NRK-52E cells treated with control scrambled siRNA or siRNA specifically targeting Adamts16. The goal of this project was to identify the downstream genes regulated by Adamts16 (the function of Adamts16 has yet to be fully delineated). Gene expression differences resulting from these siRNA-mediated gene knockdown experiments will be compared to the gene expression profiling experiments comparing kidneys from Dahl salt-senstive hypertensive inbred strain versus less hypertensive S.LEW(D1MCO4x1x3Bx1) congenic strain. The S.LEW(D1MCO4x1x3Bx1) congenic animal is an S rat containing the LEWIS allele for Adamts16 instead of the S allele. Gene expression differences in the kidneys of S.LEW(D1MCO4x1x3Bx1) versus S are hypothesized to result from sequence differences between the S and LEWIS alleles for Adamts16. It is further hypothesized that allelic differences in Adamts16 in inbred rats is responsible for blood pressure variance. The downstream genes regulated by Adamts16 may provide insight pertaining to the mechanism of blood pressure differences. Keywords: Gene knockdown with siRNA
Project description:We used Affymetrix GeneChips to expression profile kidneys from Dahl salt-senstive hypertensive inbred strain and less hypertensive S.LEW(D1MCO4x1x3Bx1) congenic strain to identify genes downstream of Adamts16 (the function of Adamts16 has yet to be fully delineated). The S.LEW(D1MCO4x1x3Bx1) congenic animal is an S rat containing the LEWIS allele for Adamts16 instead of the S allele. It is hypothesized that allelic differences in Adamts16 in inbred rats is responsible for blood pressure variance. We further hypothesize that gene expression differences in the kidneys of S.LEW(D1MCO4x1x3Bx1) versus S result from sequence differences between the S and LEWIS alleles of Adamts16. Lastly, the downstream genes differentially regulated by the Adamts16 alleles may provide insight pertaining to the mechanism of blood pressure differences. Gene expression differences resulting from these kidney comparisons will be compared to the gene expression profiling experiments comparing siRNA-mediated knockdown of Adamts16 in NRK-52E kidney cells versus scrambled siRNA control. Keywords: Genetic modification, disease state analysis
Project description:The objective of this study was to profile circular RNAs (circRNAs) in rat genetic models of cardiovascular and renal disease. Renal profiles were obtained from the Dahl Salt-Sensitive rat (S), the Dahl Salt-Resistant rat (R), the Spontaneously Hypertensive Rat (SHR) and the Wistar Kyoto rat (WKY).