Cytokines Interleukin-1β and Tumor Necrosis Factor-α Regulate Different Transcriptional and Alternative Splicing Networks in Primary β-Cells

OBJECTIVE: Cytokines contribute to pancreatic beta-cell death in type 1 diabetes. This effect is mediated by complex gene networks that remain to be characterized. We presently utilized array analysis to define the global expression pattern of genes, including spliced variants, modified by the cytokines interleukin (IL)-1beta + interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha + IFN-gamma in primary rat beta-cells. RESEARCH DESIGN AND METHODS: Fluorescence-activated cell sorter-purified rat beta-cells were exposed to IL-1beta + IFN-gamma or TNF-alpha + IFN-gamma for 6 or 24 h, and global gene expression was analyzed by microarray. Key results were confirmed by RT-PCR, and small-interfering RNAs were used to investigate the mechanistic role of novel and relevant transcription factors identified by pathway analysis. RESULTS Nearly 16,000 transcripts were detected as present in beta-cells, with temporal differences in the number of genes modulated by IL-1beta + IFNgamma or TNF-alpha + IFN-gamma. These cytokine combinations induced differential expression of inflammatory response genes, which is related to differential induction of IFN regulatory factor-7. Both treatments decreased the expression of genes involved in the maintenance of beta-cell phenotype and growth/regeneration. Cytokines induced hypoxia-inducible factor-alpha, which in this context has a proapoptotic role. Cytokines also modified the expression of >20 genes involved in RNA splicing, and exon array analysis showed cytokine-induced changes in alternative splicing of >50% of the cytokine-modified genes. CONCLUSIONS: The present study doubles the number of known genes expressed in primary beta-cells, modified or not by cytokines, and indicates the biological role for several novel cytokine-modified pathways in beta-cells. It also shows that cytokines modify alternative splicing in beta-cells, opening a new avenue of research for the field.Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe

Loss-of-activity-mutation in the cardiac chloride-bicarbonate exchanger AE3 causes short QT syndrome

Mutations in potassium and calcium channel genes have been associated with cardiac arrhythmias. Here, Jensen et al. show that an anion transporter chloride-bicarbonate exchanger AE3 is also responsible for the genetically-induced mechanism of cardiac arrhythmia, suggesting new therapeutic targets for this diseas

Tumor-specific usage of alternative transcription start sites in colorectal cancer identified by genome-wide exon array analysis

<p>Abstract</p> <p>Background</p> <p>Approximately half of all human genes use alternative transcription start sites (TSSs) to control mRNA levels and broaden the transcriptional output in healthy tissues. Aberrant expression patterns promoting carcinogenesis, however, may arise from alternative promoter usage.</p> <p>Results</p> <p>By profiling 108 colorectal samples using exon arrays, we identified nine genes (<it>TCF12, OSBPL1A, TRAK1, ANK3, CHEK1, UGP2, LMO7, ACSL5</it>, and <it>SCIN</it>) showing tumor-specific alternative TSS usage in both adenoma and cancer samples relative to normal mucosa. Analysis of independent exon array data sets corroborated these findings. Additionally, we confirmed the observed patterns for selected mRNAs using quantitative real-time reverse-transcription PCR. Interestingly, for some of the genes, the tumor-specific TSS usage was not restricted to colorectal cancer. A comprehensive survey of the nine genes in lung, bladder, liver, prostate, gastric, and brain cancer revealed significantly altered mRNA isoform ratios for <it>CHEK1, OSBPL1A</it>, and <it>TCF12 </it>in a subset of these cancer types.</p> <p>To identify the mechanism responsible for the shift in alternative TSS usage, we antagonized the Wnt-signaling pathway in DLD1 and Ls174T colorectal cancer cell lines, which remarkably led to a shift in the preferred TSS for both <it>OSBPL1A </it>and <it>TRAK1</it>. This indicated a regulatory role of the Wnt pathway in selecting TSS, possibly also involving TP53 and SOX9, as their transcription binding sites were enriched in the promoters of the tumor preferred isoforms together with their mRNA levels being increased in tumor samples.</p> <p>Finally, to evaluate the prognostic impact of the altered TSS usage, immunohistochemistry was used to show deregulation of the total protein levels of both TCF12 and OSBPL1A, corresponding to the mRNA levels observed. Furthermore, the level of nuclear TCF12 had a significant correlation to progression free survival in a cohort of 248 stage II colorectal cancer samples.</p> <p>Conclusions</p> <p>Alternative TSS usage in colorectal adenoma and cancer samples has been shown for nine genes, and <it>OSBPL1A </it>and <it>TRAK1 </it>were found to be regulated <it>in vitro </it>by Wnt signaling. TCF12 protein expression was upregulated in cancer samples and correlated with progression free survival.</p

Kapasitetskontroll av Forve bru og sanntidsovervåking

Flere bruer i dag har begrenset levetid eller kapasitet igjen. Sanntidsovervåking og etablering av digital tvilling for bruer kan gi bedre kunnskap om oppgraderinger eller endringer som er nødvendig. En av bruene som overvåkes er Forve bru fra 1938. Denne oppgaven inneholder kapasitetskontroll av Forve bru i Orkland kommune. Brua er en fagverksbru med betongdekke og ble bygd i 1938. Gjennom levetiden har den blitt oppklassifisert flere ganger og er i dag klassifisert til Bk10/60, som denne rapporten også kontrollerer mot. Oppgaven tar også for seg bruk av sanntidsovervåking, og hvordan ny teknologi kan gi en mer bærekraftig byggebransje. Brua er tegnet i Tekla for visuell fremstilling, og for å få god oversikt over brua. For å bestemme lastfordelingen i fagverket ble det videre opprettet en analysemodell i SAP2000. Modellen er kontrollert med laster i henhold til Statens vegvesens håndbok R412. Utvalgte knutepunkter ble deretter kontrollert i programmet IDEA StatiCa. Modellene ble opparbeidet på grunnlag av originale tegninger samt tidligere rapport gjennomført av Dr. Techn. Olav Olsen. Kapasitets- og stabilitetskontroll er utført ved håndberegninger i bruddgrensetilstand etter relevante Eurokoder og håndbøker. Enkelte knutepunkt ble også kontrollert ved håndberegning. Alle håndberegninger er utført ved hjelp av Mathcad eller Excel. Resultatene fra kapasitetskontrollen viser at brua kan beholde klassifiseringen Bk 10/60. I tillegg viser undersøkelsene gjort av Ferrx seg å stemme relativt godt med analysene gjort i SAP2000. Til slutt er det diskutert hvordan sanntidsovervåking kan benyttes til å forbedre datagrunnlag for dimensjonering og inspeksjon av bruer