TY - JOUR A1 - Sarukhanyan, Edita A1 - Shanmugam, Tipack Ayothyapattanam A1 - Dandekar, Thomas T1 - In silico studies reveal Peramivir and Zanamivir as an optimal drug treatment even if H7N9 avian type influenza virus acquires further resistance JF - Molecules N2 - An epidemic of avian type H7N9 influenza virus, which took place in China in 2013, was enhanced by a naturally occurring R294K mutation resistant against Oseltamivir at the catalytic site of the neuraminidase. To cope with such drug-resistant neuraminidase mutations, we applied the molecular docking technique to evaluate the fitness of the available drugs such as Oseltamivir, Zanamivir, Peramivir, Laninamivir, L-Arginine and Benserazide hydrochloride concerning the N9 enzyme with single (R294K, R119K, R372K), double (R119_294K, R119_372K, R294_372K) and triple (R119_294_372K) mutations in the pocket. We found that the drugs Peramivir and Zanamivir score best amongst the studied compounds, demonstrating their high binding potential towards the pockets with the considered mutations. Despite the fact that mutations changed the shape of the pocket and reduced the binding strength for all drugs, Peramivir was the only drug that formed interactions with the key residues at positions 119, 294 and 372 in the pocket of the triple N9 mutant, while Zanamivir demonstrated the lowest RMSD value (0.7 Å) with respect to the reference structure. KW - H7N9 influenza virus KW - neuraminidase KW - mutation KW - binding pocket KW - molecular docking Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-288240 SN - 1420-3049 VL - 27 IS - 18 ER - TY - JOUR A1 - Gupta, Shishir K. A1 - Minocha, Rashmi A1 - Thapa, Prithivi Jung A1 - Srivastava, Mugdha A1 - Dandekar, Thomas T1 - Role of the pangolin in origin of SARS-CoV-2: an evolutionary perspective JF - International Journal of Molecular Sciences N2 - After the recent emergence of SARS-CoV-2 infection, unanswered questions remain related to its evolutionary history, path of transmission or divergence and role of recombination. There is emerging evidence on amino acid substitutions occurring in key residues of the receptor-binding domain of the spike glycoprotein in coronavirus isolates from bat and pangolins. In this article, we summarize our current knowledge on the origin of SARS-CoV-2. We also analyze the host ACE2-interacting residues of the receptor-binding domain of spike glycoprotein in SARS-CoV-2 isolates from bats, and compare it to pangolin SARS-CoV-2 isolates collected from Guangdong province (GD Pangolin-CoV) and Guangxi autonomous regions (GX Pangolin-CoV) of South China. Based on our comparative analysis, we support the view that the Guangdong Pangolins are the intermediate hosts that adapted the SARS-CoV-2 and represented a significant evolutionary link in the path of transmission of SARS-CoV-2 virus. We also discuss the role of intermediate hosts in the origin of Omicron. KW - COVID-19 KW - SARS-CoV-2 KW - origin KW - evolution KW - intermediate host KW - pangolin KW - mutation KW - recombination KW - adaptation KW - transmission KW - comparative sequence analysis Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-285995 SN - 1422-0067 VL - 23 IS - 16 ER - TY - JOUR A1 - Gómez-Fernández, Paloma A1 - Lopez de Lapuente Portilla, Aitzkoa A1 - Astobiza, Ianire A1 - Mena, Jorge A1 - Urtasun, Andoni A1 - Altmann, Vivian A1 - Matesanz, Fuencisla A1 - Otaegui, David A1 - Urcelay, Elena A1 - Antigüedad, Alfredo A1 - Malhotra, Sunny A1 - Montalban, Xavier A1 - Castillo-Triviño, Tamara A1 - Espino-Paisán, Laura A1 - Aktas, Orhan A1 - Buttmann, Mathias A1 - Chan, Andrew A1 - Fontaine, Bertrand A1 - Gourraud, Pierre-Antoine A1 - Hecker, Michael A1 - Hoffjan, Sabine A1 - Kubisch, Christian A1 - Kümpfel, Tania A1 - Luessi, Felix A1 - Zettl, Uwe K. A1 - Zipp, Frauke A1 - Alloza, Iraide A1 - Comabella, Manuel A1 - Lill, Christina M. A1 - Vandenbroeck, Koen T1 - The rare IL22RA2 signal peptide coding variant rs28385692 decreases secretion of IL-22BP isoform-1, -2 and -3 and is associated with risk for multiple sclerosis JF - Cells N2 - The IL22RA2 locus is associated with risk for multiple sclerosis (MS) but causative variants are yet to be determined. In a single nucleotide polymorphism (SNP) screen of this locus in a Basque population, rs28385692, a rare coding variant substituting Leu for Pro at position 16 emerged significantly (p = 0.02). This variant is located in the signal peptide (SP) shared by the three secreted protein isoforms produced by IL22RA2 (IL-22 binding protein-1(IL-22BPi1), IL-22BPi2 and IL-22BPi3). Genotyping was extended to a Europe-wide case-control dataset and yielded high significance in the full dataset (p = 3.17 × 10\(^{-4}\)). Importantly, logistic regression analyses conditioning on the main known MS-associated SNP at this locus, rs17066096, revealed that this association was independent from the primary association signal in the full case-control dataset. In silico analysis predicted both disruption of the alpha helix of the H-region of the SP and decreased hydrophobicity of this region, ultimately affecting the SP cleavage site. We tested the effect of the p.Leu16Pro variant on the secretion of IL-22BPi1, IL-22BPi2 and IL-22BPi3 and observed that the Pro16 risk allele significantly lowers secretion levels of each of the isoforms to around 50%–60% in comparison to the Leu16 reference allele. Thus, our study suggests that genetically coded decreased levels of IL-22BP isoforms are associated with augmented risk for MS. KW - IL22RA2 KW - IL-22 binding protein isoform KW - mutation KW - signal peptide KW - multiple sclerosis KW - autoimmune Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-200769 SN - 2073-4409 VL - 9 IS - 1 ER - TY - JOUR A1 - Grünewald, Benedikt A1 - Lange, Maren D A1 - Werner, Christian A1 - O'Leary, Aet A1 - Weishaupt, Andreas A1 - Popp, Sandy A1 - Pearce, David A A1 - Wiendl, Heinz A1 - Reif, Andreas A1 - Pape, Hans C A1 - Toyka, Klaus V A1 - Sommer, Claudia A1 - Geis, Christian T1 - Defective synaptic transmission causes disease signs in a mouse model of juvenile neuronal ceroid lipofuscinosis JF - eLife N2 - Juvenile neuronal ceroid lipofuscinosis (JNCL or Batten disease) caused by mutations in the CLN3 gene is the most prevalent inherited neurodegenerative disease in childhood resulting in widespread central nervous system dysfunction and premature death. The consequences of CLN3 mutation on the progression of the disease, on neuronal transmission, and on central nervous network dysfunction are poorly understood. We used Cln3 knockout (Cln3\(^{Δex1-6}\)) mice and found increased anxiety-related behavior and impaired aversive learning as well as markedly affected motor function including disordered coordination. Patch-clamp and loose-patch recordings revealed severely affected inhibitory and excitatory synaptic transmission in the amygdala, hippocampus, and cerebellar networks. Changes in presynaptic release properties may result from dysfunction of CLN3 protein. Furthermore, loss of calbindin, neuropeptide Y, parvalbumin, and GAD65-positive interneurons in central networks collectively support the hypothesis that degeneration of GABAergic interneurons may be the cause of supraspinal GABAergic disinhibition. KW - CLN3 KW - mutation KW - mouse model KW - synaptic transmission KW - amygdala KW - hippocampus Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-170004 VL - 6 IS - e28685 ER - TY - JOUR A1 - Wolf, Beat A1 - Kuonen, Pierre A1 - Dandekar, Thomas A1 - Atlan, David T1 - DNAseq workflow in a diagnostic context and an example of a user friendly implementation JF - BioMed Research International N2 - Over recent years next generation sequencing (NGS) technologies evolved from costly tools used by very few, to a much more accessible and economically viable technology. Through this recently gained popularity, its use-cases expanded from research environments into clinical settings. But the technical know-how and infrastructure required to analyze the data remain an obstacle for a wider adoption of this technology, especially in smaller laboratories. We present GensearchNGS, a commercial DNAseq software suite distributed by Phenosystems SA. The focus of GensearchNGS is the optimal usage of already existing infrastructure, while keeping its use simple. This is achieved through the integration of existing tools in a comprehensive software environment, as well as custom algorithms developed with the restrictions of limited infrastructures in mind. This includes the possibility to connect multiple computers to speed up computing intensive parts of the analysis such as sequence alignments. We present a typical DNAseq workflow for NGS data analysis and the approach GensearchNGS takes to implement it. The presented workflow goes from raw data quality control to the final variant report. This includes features such as gene panels and the integration of online databases, like Ensembl for annotations or Cafe Variome for variant sharing. KW - next generation sequencing KW - genome browser KW - mutation KW - algorithm KW - database KW - format KW - discovery KW - exome KW - variants KW - alignment Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-144527 IS - 403497 ER - TY - JOUR A1 - Wang Ip, Chi A1 - Klaus, Laura-Christin A1 - Karikari, Akua A. A1 - Visanji, Naomi P. A1 - Brotchie, Jonathan M. A1 - Lang, Anthony E. A1 - Volkmann, Jens A1 - Koprich, James B. T1 - AAV1/2-induced overexpression of A53T-α-synuclein in the substantia nigra results in degeneration of the nigrostriatal system with Lewy-like pathology and motor impairment: a new mouse model for Parkinson’s disease JF - Acta Neuropathologica Communications N2 - α-Synuclein is a protein implicated in the etiopathogenesis of Parkinson’s disease (PD). AAV1/2-driven overexpression of human mutated A53T-α-synuclein in rat and monkey substantia nigra (SN) induces degeneration of nigral dopaminergic neurons and decreases striatal dopamine and tyrosine hydroxylase (TH). Given certain advantages of the mouse, especially it being amendable to genetic manipulation, translating the AAV1/2-A53T α-synuclein model to mice would be of significant value. AAV1/2-A53T α-synuclein or AAV1/2 empty vector (EV) at a concentration of 5.16 x 10\(^{12}\) gp/ml were unilaterally injected into the right SN of male adult C57BL/6 mice. Post-mortem examinations included immunohistochemistry to analyze nigral α-synuclein, Ser129 phosphorylated α-synuclein and TH expression, striatal dopamine transporter (DAT) levels by autoradiography and dopamine levels by high performance liquid chromatography. At 10 weeks, in AAV1/2-A53T α-synuclein mice there was a 33% reduction in TH+ dopaminergic nigral neurons (P < 0.001), 29% deficit in striatal DAT binding (P < 0.05), 38% and 33% reductions in dopamine (P < 0.001) and DOPAC (P < 0.01) levels and a 60% increase in dopamine turnover (homovanilic acid/dopamine ratio; P < 0.001). Immunofluorescence showed that the AAV1/2-A53T α-synuclein injected mice had widespread nigral and striatal expression of vector-delivered A53T-α-synuclein. Concurrent staining with human PD SN samples using gold standard histological methodology for Lewy pathology detection by proteinase K digestion and application of specific antibody raised against human Lewy body α-synuclein (LB509) and Ser129 phosphorylated α-synuclein (81A) revealed insoluble α-synuclein aggregates in AAV1/2-A53T α-synuclein mice resembling Lewy-like neurites and bodies. In the cylinder test, we observed significant paw use asymmetry in the AAV1/2-A53T α-synuclein group when compared to EV controls at 5 and 9 weeks post injection (P < 0.001; P < 0.05). These data show that unilateral injection of AAV1/2-A53T α-synuclein into the mouse SN leads to persistent motor deficits, neurodegeneration of the nigrostriatal dopaminergic system and development of Lewy-like pathology, thereby reflecting clinical and pathological hallmarks of human PD. KW - Lewy-like pathology KW - Parkinson’s disease KW - α-synuclein KW - A53T KW - mutation KW - mouse model Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-159429 VL - 5 IS - 11 ER - TY - JOUR A1 - Hampe, Irene A. I. A1 - Friedman, Justin A1 - Edgerton, Mira A1 - Morschhäuser, Joachim T1 - An acquired mechanism of antifungal drug resistance simultaneously enables Candida albicans to escape from intrinsic host defenses JF - PLoS Pathogens N2 - The opportunistic fungal pathogen Candida albicans frequently produces genetically altered variants to adapt to environmental changes and new host niches in the course of its life-long association with the human host. Gain-of-function mutations in zinc cluster transcription factors, which result in the constitutive upregulation of their target genes, are a common cause of acquired resistance to the widely used antifungal drug fluconazole, especially during long-term therapy of oropharyngeal candidiasis. In this study, we investigated if C. albicans also can develop resistance to the antimicrobial peptide histatin 5, which is secreted in the saliva of humans to protect the oral mucosa from pathogenic microbes. As histatin 5 has been shown to be transported out of C. albicans cells by the Flu1 efflux pump, we screened a library of C. albicans strains that contain artificially activated forms of all zinc cluster transcription factors of this fungus for increased FLU1 expression. We found that a hyperactive Mrr1, which confers fluconazole resistance by upregulating the multidrug efflux pump MDR1 and other genes, also causes FLU1 overexpression. Similarly to the artificially activated Mrr1, naturally occurring gain-of-function mutations in this transcription factor also caused FLU1 upregulation and increased histatin 5 resistance. Surprisingly, however, Mrr1-mediated histatin 5 resistance was mainly caused by the upregulation of MDR1 instead of FLU1, revealing a previously unrecognized function of the Mdr1 efflux pump. Fluconazole-resistant clinical C. albicans isolates with different Mrr1 gain-of-function mutations were less efficiently killed by histatin 5, and this phenotype was reverted when MRR1 was deleted. Therefore, antimycotic therapy can promote the evolution of strains that, as a consequence of drug resistance mutations, simultaneously have acquired increased resistance against an innate host defense mechanism and are thereby better adapted to certain host niches. KW - antimicrobial resistance KW - transcriptional control KW - Candida albicans KW - transcription factors KW - mutation KW - hyperexpression techniques KW - antifungals KW - point mutation Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-158883 VL - 13 IS - 9 ER - TY - JOUR A1 - Roesler, Joachim A1 - Segerer, Florian A1 - Morbach, Henner A1 - Kleinert, Stefan A1 - Thieme, Sebastian A1 - Rösen-Wolff, Angela A1 - Liese, Johannes G. T1 - P67-phox (NCF2) Lacking Exons 11 and 12 Is Functionally Active and Leads to an Extremely Late Diagnosis of Chronic Granulomatous Disease (CGD) JF - PLoS One N2 - Two brothers in their fifties presented with a medical history of suspected fungal allergy, allergic bronchopulmonary aspergillosis, alveolitis, and invasive aspergillosis and pulmonary fistula, respectively. Eventually, after a delay of 50 years, chronic granulomatous disease (CGD) was diagnosed in the index patient. We found a new splice mutation in the NCF2 (p67-phox) gene, c.1000+2T -> G, that led to several splice products one of which lacked exons 11 and 12. This deletion was in frame and allowed for remarkable residual NADPH oxidase activity as determined by transduction experiments using a retroviral vector. We conclude that p67-phox which lacks the 34 amino acids encoded by the two exons can still exert considerable functional activity. This activity can partially explain the long-term survival of the patients without adequate diagnosis and treatment, but could not prevent progressing lung damage. KW - P67(PHOX) KW - NADPH oxidase KW - European experience KW - interferon gamma KW - gene KW - region KW - prophylaxis KW - infection KW - mutation Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-134948 VL - 7 IS - 4 ER - TY - JOUR A1 - Sbiera, Silviu A1 - Tryfonidou, Marianna A. A1 - Weigand, Isabel A1 - Grinwis, Guy C. M. A1 - Broeckx, Bart A1 - Herterich, Sabine A1 - Allolio, Bruno A1 - Deutschbein, Timo A1 - Fassnacht, Martin A1 - Meij, Björn P. T1 - Lack of Ubiquitin Specific Protease 8 (USP8) Mutations in Canine Corticotroph Pituitary Adenomas JF - Plos One N2 - Purpose Cushing’s disease (CD), also known as pituitary-dependent hyperadrenocorticism, is caused by adrenocorticotropic hormone (ACTH)-secreting pituitary tumours. Affected humans and dogs have similar clinical manifestations, however, the incidence of the canine disease is thousand-fold higher. This makes the dog an obvious model for studying the pathogenesis of pituitary-dependent hyperadrenocorticism. Despite certain similarities identified at the molecular level, the question still remains whether the two species have a shared oncogenetic background. Recently, hotspot recurrent mutations in the gene encoding for ubiquitin specific protease 8 (USP8) have been identified as the main driver behind the formation of ACTH-secreting pituitary adenomas in humans. In this study, we aimed to verify whether USP8 mutations also play a role in the development of such tumours in dogs. Methods Presence of USP8 mutations was analysed by Sanger and PCR-cloning sequencing in 38 canine ACTH-secreting adenomas. Furthermore, the role of USP8 and EGFR protein expression was assessed by immunohistochemistry in a subset of 25 adenomas. Results None of the analysed canine ACTH-secreting adenomas presented mutations in the USP8 gene. In a subset of these adenomas, however, we observed an increased nuclear expression of USP8, a phenotype characteristic for the USP8 mutated human tumours, that correlated with smaller tumour size but elevated ACTH production in those tumours. Conclusions Canine ACTH-secreting pituitary adenomas lack mutations in the USP8 gene suggesting a different genetic background of pituitary tumourigenesis in dogs. However, elevated nuclear USP8 protein expression in a subset of tumours was associated with a similar phenotype as in their human counterparts, indicating a possible end-point convergence of the different genetic backgrounds in the two species. In order to establish the dog as a useful animal model for the study of CD, further comprehensive studies are needed. KW - cytoplasmic staining KW - dogs KW - adenomas KW - pituitary gland KW - pituitary adenomas KW - nuclear staining KW - mutation KW - protein expression Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-148020 VL - 11 IS - 12 ER - TY - JOUR A1 - Subramanian, Hariharan A1 - Döring, Frank A1 - Kollert, Sina A1 - Rukoyatkina, Natalia A1 - Sturm, Julia A1 - Gambaryan, Stepan A1 - Stellzig-Eisenhauer, Angelika A1 - Meyer-Marcotty, Philipp A1 - Eigenthaler, Martin A1 - Wischmeyer, Erhard T1 - PTH1R Mutants Found in Patients with Primary Failure of Tooth Eruption Disrupt G-Protein Signaling JF - PLoS One N2 - Aim Primary failure of tooth eruption (PFE) is causally linked to heterozygous mutations of the parathyroid hormone receptor (PTH1R) gene. The mutants described so far lead to exchange of amino acids or truncation of the protein that may result in structural changes of the expressed PTH1R. However, functional effects of these mutations have not been investigated yet. Materials and Methods In HEK293 cells, PTH1R wild type was co-transfected with selected PTH1R mutants identified in patients with PFE. The effects on activation of PTH-regulated intracellular signaling pathways were analyzed by ELISA and Western immunoblotting. Differential effects of wild type and mutated PTH1R on TRESK ion channel regulation were analyzed by electrophysiological recordings in Xenopus laevis oocytes. Results In HEK293 cells, activation of PTH1R wild type increases cAMP and in response activates cAMP-stimulated protein kinase as detected by phosphorylation of the vasodilator stimulated phosphoprotein (VASP). In contrast, the PTH1R mutants are functionally inactive and mutant PTH1R/Gly452Glu has a dominant negative effect on the signaling of PTH1R wild type. Confocal imaging revealed that wild type PTH1R is expressed on the cell surface, whereas PTH1R/Gly452Glu mutant is mostly retained inside the cell. Furthermore, in contrast to wild type PTH1R which substantially augmented K+ currents of TRESK channels, coupling of mutated PTH1R to TRESK channels was completely abolished. Conclusions PTH1R mutations affect intracellular PTH-regulated signaling in vitro. In patients with primary failure of tooth eruption defective signaling of PTH1R mutations is suggested to occur in dento-alveolar cells and thus may lead to impaired tooth movement. KW - phosphorylation KW - xenopus oocytes KW - calcium signaling KW - intracellular receptors KW - mutation KW - teeth KW - tooth eruption KW - transfection Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-147967 VL - 11 IS - 11 ER - TY - JOUR A1 - Galimberti, Daniela A1 - Dell'Osso, Bernardo A1 - Fenoglio, Chiara A1 - Villa, Chiara A1 - Cortini, Francesca A1 - Serpente, Maria A1 - Kittel-Schneider, Sarah A1 - Weigl, Johannes A1 - Neuner, Maria A1 - Volkert, Juliane A1 - Leonhard, C. A1 - Olmes, David G. A1 - Kopf, Juliane A1 - Cantoni, Claudia A1 - Ridolfi, Elisa A1 - Palazzo, Carlotta A1 - Ghezzi, Laura A1 - Bresolin, Nereo A1 - Altamura, A.C. A1 - Scarpini, Elio A1 - Reif, Andreas T1 - Progranulin Gene Variability and Plasma Levels in Bipolar Disorder and Schizophrenia JF - PLoS One N2 - Basing on the assumption that frontotemporal lobar degeneration (FTLD), schizophrenia and bipolar disorder (BPD) might share common aetiological mechanisms, we analyzed genetic variation in the FTLD risk gene progranulin (GRN) in a German population of patients with schizophrenia (n=271) or BPD (n=237) as compared with 574 age-, gender-and ethnicity-matched controls. Furthermore, we measured plasma progranulin levels in 26 German BPD patients as well as in 61 Italian BPD patients and 29 matched controls. A significantly decreased allelic frequency of the minor versus the wild-type allele was observed for rs2879096 (23.2 versus 34.2%, P<0.001, OR: 0.63, 95% CI: 0.49-0.80), rs4792938 (30.7 versus 39.7%, P=0.005, OR: 0.70, 95% CI: 0.55-0.89) and rs5848 (30.3 versus 36.8, P=0.007, OR: 0.71, 95% CI: 0.56-0.91). Mean +/- SEM progranulin plasma levels were significantly decreased in BPD patients, either Germans or Italians, as compared with controls (89.69 +/- 3.97 and 116.14 +/- 5.80 ng/ml, respectively, versus 180.81 +/- 18.39 ng/ml P<0.001) and were not correlated with age. In conclusion, GRN variability decreases the risk to develop BPD and schizophrenia, and progranulin plasma levels are significantly lower in BPD patients than in controls. Nevertheless, a larger replication analysis would be needed to confirm these preliminary results. KW - people KW - frontotemporal lobar degeneration KW - genome-wide association KW - Alzheimers disease KW - risk genes KW - dementia KW - GRN KW - mutation KW - families KW - linkage Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-131910 VL - 7 IS - 4 ER - TY - JOUR A1 - Böhm, Johann A1 - Vasli, Nasim A1 - Maurer, Marie A1 - Cowling, Belinda A1 - Shelton, G. Diane A1 - Kress, Wolfram A1 - Toussaint, Anne A1 - Prokic, Ivana A1 - Schara, Ulrike A1 - Anderson, Thomas James A1 - Weis, Joachim A1 - Tiret, Laurent A1 - Laporte, Jocelyn T1 - Altered Splicing of the BIN1 Muscle-Specific Exon in Humans and Dogs with Highly Progressive Centronuclear Myopathy JF - PLOS Genetics N2 - Amphiphysin 2, encoded by BIN1, is a key factor for membrane sensing and remodelling in different cell types. Homozygous BIN1 mutations in ubiquitously expressed exons are associated with autosomal recessive centronuclear myopathy (CNM), a mildly progressive muscle disorder typically showing abnormal nuclear centralization on biopsies. In addition, misregulation of BIN1 splicing partially accounts for the muscle defects in myotonic dystrophy (DM). However, the muscle-specific function of amphiphysin 2 and its pathogenicity in both muscle disorders are not well understood. In this study we identified and characterized the first mutation affecting the splicing of the muscle-specific BIN1 exon 11 in a consanguineous family with rapidly progressive and ultimately fatal centronuclear myopathy. In parallel, we discovered a mutation in the same BIN1 exon 11 acceptor splice site as the genetic cause of the canine Inherited Myopathy of Great Danes (IMGD). Analysis of RNA from patient muscle demonstrated complete skipping of exon 11 and BIN1 constructs without exon 11 were unable to promote membrane tubulation in differentiated myotubes. Comparative immunofluorescence and ultrastructural analyses of patient and canine biopsies revealed common structural defects, emphasizing the importance of amphiphysin 2 in membrane remodelling and maintenance of the skeletal muscle triad. Our data demonstrate that the alteration of the muscle-specific function of amphiphysin 2 is a common pathomechanism for centronuclear myopathy, myotonic dystrophy, and IMGD. The IMGD dog is the first faithful model for human BIN1-related CNM and represents a mammalian model available for preclinical trials of potential therapies. KW - linked myotubular myopathy KW - skeletal muscle KW - inherited myopathy KW - SH3 domain KW - amphiphysin-2 BIN1 KW - membrane curvature KW - tumor-suppressor KW - great dane KW - mutation KW - gene Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-127590 SN - 1553-7404 VL - 9 IS - 6 ER - TY - JOUR A1 - Walter, Maggie C. A1 - Reilich, Peter A1 - Thiele, Simone A1 - Schessl, Joachim A1 - Schreiber, Herbert A1 - Reiners, Karlheinz A1 - Kress, Wolfram A1 - Müller-Reible, Clemens A1 - Vorgerd, Matthias A1 - Urban, Peter A1 - Schrank, Bertold A1 - Deschauer, Marcus A1 - Schlotter-Weigel, Beate A1 - Kohnen, Ralf A1 - Lochmüller, Hans T1 - Treatment of dysferlinopathy with deflazacort: a double-blind, placebo-controlled clinical trial JF - Orphanet Journal of Rare Diseases N2 - Background: Dysferlinopathies are autosomal recessive disorders caused by mutations in the dysferlin (DYSF) gene encoding the dysferlin protein. DYSF mutations lead to a wide range of muscular phenotypes, with the most prominent being Miyoshi myopathy (MM) and limb girdle muscular dystrophy type 2B (LGMD2B). Methods: We assessed the one-year-natural course of dysferlinopathy, and the safety and efficacy of deflazacort treatment in a double-blind, placebo-controlled cross-over trial. After one year of natural course without intervention, 25 patients with genetically defined dysferlinopathy were randomized to receive deflazacort and placebo for six months each (1 mg/kg/day in month one, 1 mg/kg every 2nd day during months two to six) in one of two treatment sequences. Results: During one year of natural course, muscle strength declined about 2% as measured by CIDD (Clinical Investigation of Duchenne Dystrophy) score, and 76 Newton as measured by hand-held dynamometry. Deflazacort did not improve muscle strength. In contrast, there is a trend of worsening muscle strength under deflazacort treatment, which recovers after discontinuation of the study drug. During deflazacort treatment, patients showed a broad spectrum of steroid side effects. Conclusion: Deflazacort is not an effective therapy for dysferlinopathies, and off-label use is not warranted. This is an important finding, since steroid treatment should not be administered in patients with dysferlinopathy, who may be often misdiagnosed as polymyositis. KW - Deflazacort KW - muscle strength KW - gridle muscular-dystrophy KW - Duchenne dystrphy KW - Miyoshi myopathy KW - mutation KW - prednisone KW - gene KW - 2B KW - children KW - design KW - steroids KW - therapy KW - dysferlinopathy KW - Limb girdle muscular dystrophy (LGMD) Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125663 SN - 1750-1172 VL - 8 IS - 26 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 -