TY - JOUR A1 - Gewies, Andreas A1 - Gorka, Oliver A1 - Bergmann, Hanna A1 - Pechloff, Konstanze A1 - Petermann, Franziska A1 - Jeltsch, Katharina M. A1 - Rudelius, Martina A1 - Kriegsmann, Mark A1 - Weichert, Wilko A1 - Horsch, Marion A1 - Beckers, Johannes A1 - Wurst, Wolfgang A1 - Heikenwalder, Mathias A1 - Korn, Thomas A1 - Heissmeyer, Vigo A1 - Ruland, Juergen T1 - Uncoupling Malt1 Threshold Function from Paracaspase Activity Results in Destructive Autoimmune Inflammation JF - Cell Reports N2 - The paracaspase Malt1 is a central regulator of antigen receptor signaling that is frequently mutated in human lymphoma. As a scaffold, it assembles protein complexes for NF-kappa B activation, and its proteolytic domain cleaves negative NF-kappa B regulators for signal enforcement. Still, the physiological functions of Malt1-protease are unknown. We demonstrate that targeted Malt1-paracaspase inactivation induces a lethal inflammatory syndrome with lymphocyte-dependent neurodegeneration in vivo. Paracaspase activity is essential for regulatory T cell (Treg) and innate-like B cell development, but it is largely dispensable for overcoming Malt1-dependent thresholds for lymphocyte activation. In addition to NF-kappa B inhibitors, Malt1 cleaves an entire set of mRNA stability regulators, including Roquin-1, Roquin-2, and Regnase-1, and paracaspase inactivation results in excessive interferon gamma (IFN gamma) production by effector lymphocytes that drive pathology. Together, our results reveal distinct threshold and modulatory functions of Malt1 that differentially control lymphocyte differentiation and activation pathways and demonstrate that selective paracaspase blockage skews systemic immunity toward destructive autoinflammation. KW - helper T-cells KW - combined immunodeficiency KW - messenger RNA KW - roquin KW - mice KW - NF-KAPPA-B KW - lymphoid-tissue KW - activation KW - cleavage KW - mutations Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-114627 VL - 9 IS - 4 ER - TY - JOUR A1 - Reynolds, David A1 - Cliffe, Laura A1 - Förstner, Konrad U. A1 - Hon, Chung-Chau A1 - Siegel, T. Nicolai A1 - Sabatini, Robert T1 - Regulation of transcription termination by glucosylated hydroxymethyluracil, base J, in Leishmania major and Trypanosoma brucei JF - Nucleic Acids Research N2 - Base J, beta-d-glucosyl-hydroxymethyluracil, is an epigenetic modification of thymine in the nuclear DNA of flagellated protozoa of the order Kinetoplastida. J is enriched at sites involved in RNA polymerase ( RNAP) II initiation and termination. Reduction of J in Leishmania tarentolae via growth in BrdU resulted in cell death and indicated a role of J in the regulation of RNAP II termination. To further explore J function in RNAP II termination among kinetoplastids and avoid indirect effects associated with BrdU toxicity and genetic deletions, we inhibited J synthesis in Leishmania major and Trypanosoma brucei using DMOG. Reduction of J in L. major resulted in genome-wide defects in transcription termination at the end of polycistronic gene clusters and the generation of antisense RNAs, without cell death. In contrast, loss of J in T. brucei did not lead to genome-wide termination defects; however, the loss of J at specific sites within polycistronic gene clusters led to altered transcription termination and increased expression of downstream genes. Thus, J regulation of RNAP II transcription termination genome-wide is restricted to Leishmania spp., while in T. brucei it regulates termination and gene expression at specific sites within polycistronic gene clusters. KW - RNA-polymerase-II KW - variant surface glycoprotein KW - SWI2/SNF2-like protein KW - messenger RNA KW - polycistronic transcription KW - DNA glycosation KW - hela cells KW - gene expression KW - genome KW - 5-bromodeoxyuridine Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-117863 VL - 42 IS - 15 ER - TY - JOUR A1 - Petrasek, Tomas A1 - Prokopova, Iva A1 - Sladek, Martin A1 - Weissova, Kamila A1 - Vojtechova, Iveta A1 - Bahnik, Stepan A1 - Zemanova, Anna A1 - Schönig, Kai A1 - Berger, Stefan A1 - Tews, Bjoern A1 - Bartsch, Dusan A1 - Schwab, Martin E. A1 - Sumova, Alena A1 - Stuchlik, Ales T1 - Nogo-A-deficient transgenic rats show deficits in higher cognitive functions, decreased anxiety, and altered circadian activity patterns JF - Frontiers in Behavioral Neuroscience N2 - Decreased levels of Nogo-A-dependent signaling have been shown to affect behavior and cognitive functions. In Nogo-A knockout and knockdown laboratory rodents, behavioral alterations were observed, possibly corresponding with human neuropsychiatric diseases of neurodevelopmental origin, particularly schizophrenia. This study offers further insight into behavioral manifestations of Nogo-A knockdown in laboratory rats, focusing on spatial and non-spatial cognition, anxiety levels, circadian rhythmicity, and activity patterns. Demonstrated is an impairment of cognitive functions and behavioral flexibility in a spatial active avoidance task, while non-spatial memory in a step-through avoidance task was spared. No signs of anhedonia, typical for schizophrenic patients, were observed in the animals. Some measures indicated lower anxiety levels in the Nogo-A-deficient group. Circadian rhythmicity in locomotor activity was preserved in the Nogo-A knockout rats and their circadian period (tau) did not differ from controls. However, daily activity patterns were slightly altered in the knockdown animals. We conclude that a reduction of Nogo-A levels induces changes in CNS development, manifested as subtle alterations in cognitive functions, emotionality, and activity patterns. KW - AAPA KW - circadian rhythmicity KW - passive avoidance KW - Nogo-A KW - anhedonia KW - neophobia KW - morris water maze KW - place avoidance task KW - neurite outgrowth inhibitor KW - axon regeneration KW - synaptic plasticity KW - down regulation KW - traumatic brain injury KW - carousel maze KW - messenger RNA KW - genetic deletion Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-117073 VL - 8 IS - 90 ER - TY - JOUR A1 - Linder, Bastian A1 - Hirmer, Anja A1 - Gal, Andreas A1 - Rüther, Klaus A1 - Bolz, Hanno Jörn A1 - Winkler, Christoph A1 - Laggerbauer, Bernhard A1 - Fischer, Utz T1 - Identification of a PRPF4 Loss-of-Function Variant That Abrogates U4/U6.U5 Tri-snRNP Integration and Is Associated with Retinitis Pigmentosa N2 - Pre-mRNA splicing by the spliceosome is an essential step in the maturation of nearly all human mRNAs. Mutations in six spliceosomal proteins, PRPF3, PRPF4, PRPF6, PRPF8, PRPF31 and SNRNP200, cause retinitis pigmentosa (RP), a disease characterized by progressive photoreceptor degeneration. All splicing factors linked to RP are constituents of the U4/U6.U5 tri-snRNP subunit of the spliceosome, suggesting that the compromised function of this particle may lead to RP. Here, we report the identification of the p.R192H variant of the tri-snRNP factor PRPF4 in a patient with RP. The mutation affects a highly conserved arginine residue that is crucial for PRPF4 function. Introduction of a corresponding mutation into the zebrafish homolog of PRPF4 resulted in a complete loss of function in vivo. A series of biochemical experiments suggested that p.R192H disrupts the binding interface between PRPF4 and its interactor PRPF3. This interferes with the ability of PRPF4 to integrate into the tri-snRNP, as shown in a human cell line and in zebrafish embryos. These data suggest that the p.R192H variant of PRPF4 represents a functional null allele. The resulting haploinsufficiency of PRPF4 compromises the function of the tri-snRNP, reinforcing the notion that this spliceosomal particle is of crucial importance in the physiology of the retina. KW - zebrafish KW - embryos KW - immunoprecipitation KW - arginine KW - messenger RNA KW - spliceosomes KW - mutation KW - RNA splicing Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-113663 ER -