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 - Geyer, Kathrin K. A1 - Chalmers, Iain W. A1 - MacKintosh, Neil A1 - Hirst, Julie E. A1 - Geoghegan, Rory A1 - Badets, Mathieu A1 - Brophy, Peter M. A1 - Brehm, Klaus A1 - Hoffmann, Karl F. T1 - Cytosine methylation is a conserved epigenetic feature found throughout the phylum Platyhelminthes JF - BMC Genomics N2 - Background: The phylum Platyhelminthes (flatworms) contains an important group of bilaterian organisms responsible for many debilitating and chronic infectious diseases of human and animal populations inhabiting the planet today. In addition to their biomedical and veterinary relevance, some platyhelminths are also frequently used models for understanding tissue regeneration and stem cell biology. Therefore, the molecular (genetic and epigenetic) characteristics that underlie trophic specialism, pathogenicity or developmental maturation are likely to be pivotal in our continued studies of this important metazoan group. Indeed, in contrast to earlier studies that failed to detect evidence of cytosine or adenine methylation in parasitic flatworm taxa, our laboratory has recently defined a critical role for cytosine methylation in Schistosoma mansoni oviposition, egg maturation and ovarian development. Thus, in order to identify whether this epigenetic modification features in other platyhelminth species or is a novelty of S. mansoni, we conducted a study simultaneously surveying for DNA methylation machinery components and DNA methylation marks throughout the phylum using both parasitic and non-parasitic representatives. Results: Firstly, using both S. mansoni DNA methyltransferase 2 (SmDNMT2) and methyl-CpG binding domain protein (SmMBD) as query sequences, we illustrate that essential DNA methylation machinery components are well conserved throughout the phylum. Secondly, using both molecular (methylation specific amplification polymorphism, MSAP) and immunological (enzyme-linked immunoabsorbent assay, ELISA) methodologies, we demonstrate that representative species (Echinococcus multilocularis, Protopolystoma xenopodis, Schistosoma haematobium, Schistosoma japonicum, Fasciola hepatica and Polycelis nigra) within all four platyhelminth classes (Cestoda, Monogenea, Trematoda and 'Turbellaria') contain methylated cytosines within their genome compartments. Conclusions: Collectively, these findings provide the first direct evidence for a functionally conserved and enzymatically active DNA methylation system throughout the Platyhelminthes. Defining how this epigenetic feature shapes phenotypic diversity and development within the phylum represents an exciting new area of metazoan biology. KW - methyltransferase homolog KW - echinococcus multilocularis KW - platyhelminthes KW - 5-methyl cytosine KW - gene KW - proteins KW - stem cells KW - maximum liklihood KW - schistoma mansoni KW - flatworm KW - CPG binding domain KW - DNA methylation KW - epgenetics KW - complex Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-121892 SN - 1471-2164 VL - 14 IS - 462 ER - TY - JOUR A1 - Makgotlho, Phuti E. A1 - Marincola, Gabriella A1 - Schäfer, Daniel A1 - Liu, Quian A1 - Bae, Taeok A1 - Geiger, Tobias A1 - Wasserman, Elizabeth A1 - Wolz, Christine A1 - Ziebuhr, Wilma A1 - Sinha, Bhanu T1 - SDS Interferes with SaeS Signaling of Staphylococcus aureus Independently of SaePQ JF - PLOS ONE N2 - The Staphylococcus aureus regulatory saePQRS system controls the expression of numerous virulence factors, including extracellular adherence protein (Eap), which amongst others facilitates invasion of host cells. The saePQRS operon codes for 4 proteins: the histidine kinase SaeS, the response regulator SaeR, the lipoprotein SaeP and the transmembrane protein SaeQ. S. aureus strain Newman has a single amino acid substitution in the transmembrane domain of SaeS (L18P) which results in constitutive kinase activity. SDS was shown to be one of the signals interfering with SaeS activity leading to inhibition of the sae target gene eap in strains with SaeS(L) but causing activation in strains containing SaeS(P). Here, we analyzed the possible involvement of the SaeP protein and saePQ region in SDS-mediated sae/eap expression. We found that SaePQ is not needed for SDS-mediated SaeS signaling. Furthermore, we could show that SaeS activity is closely linked to the expression of Eap and the capacity to invade host cells in a number of clinical isolates. This suggests that SaeS activity might be directly modulated by structurally non-complex environmental signals, as SDS, which possibly altering its kinase/phosphatase activity. KW - host-cell invasion KW - 2-component system KW - strain Newman KW - allelic replacement KW - genome sequence KW - locus KW - gene KW - activation KW - expression KW - infection Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-128469 SN - 1932-6203 VL - 8 IS - 8 ER - TY - JOUR A1 - Palige, Katja A1 - Linde, Jörg A1 - Martin, Ronny A1 - Böttcher, Bettina A1 - Citiulo, Francesco A1 - Sullivan, Derek J. A1 - Weber, Johann A1 - Staib, Claudia A1 - Rupp, Steffen A1 - Hube, Bernhard A1 - Morschhäuser, Joachim A1 - Staib, Peter T1 - Global Transcriptome Sequencing Identifies Chlamydospore Specific Markers in Candida albicans and Candida dubliniensis JF - PLoS ONE N2 - Candida albicans and Candida dubliniensis are pathogenic fungi that are highly related but differ in virulence and in some phenotypic traits. During in vitro growth on certain nutrient-poor media, C. albicans and C. dubliniensis are the only yeast species which are able to produce chlamydospores, large thick-walled cells of unknown function. Interestingly, only C. dubliniensis forms pseudohyphae with abundant chlamydospores when grown on Staib medium, while C. albicans grows exclusively as a budding yeast. In order to further our understanding of chlamydospore development and assembly, we compared the global transcriptional profile of both species during growth in liquid Staib medium by RNA sequencing. We also included a C. albicans mutant in our study which lacks the morphogenetic transcriptional repressor Nrg1. This strain, which is characterized by its constitutive pseudohyphal growth, specifically produces masses of chlamydospores in Staib medium, similar to C. dubliniensis. This comparative approach identified a set of putatively chlamydospore-related genes. Two of the homologous C. albicans and C. dubliniensis genes (CSP1 and CSP2) which were most strongly upregulated during chlamydospore development were analysed in more detail. By use of the green fluorescent protein as a reporter, the encoded putative cell wall related proteins were found to exclusively localize to C. albicans and C. dubliniensis chlamydospores. Our findings uncover the first chlamydospore specific markers in Candida species and provide novel insights in the complex morphogenetic development of these important fungal pathogens. KW - NRG1 KW - staib agar KW - gene KW - morphogenesis KW - expression KW - regulator KW - virulence KW - growth KW - UME6 KW - epidemiology Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-131007 VL - 8 IS - 4 ER - TY - JOUR A1 - Szabó, Áron A1 - Papin, Christian A1 - Zorn, Daniela A1 - Ponien, Prishila A1 - Weber, Frank A1 - Raabe, Thomas A1 - Rouyer, François T1 - The CK2 Kinase Stabilizes CLOCK and Represses Its Activity in the Drosophila Circadian Oscillator JF - PLoS Biology N2 - Phosphorylation is a pivotal regulatory mechanism for protein stability and activity in circadian clocks regardless of their evolutionary origin. It determines the speed and strength of molecular oscillations by acting on transcriptional activators and their repressors, which form negative feedback loops. In Drosophila, the CK2 kinase phosphorylates and destabilizes the PERIOD (PER) and TIMELESS (TIM) proteins, which inhibit CLOCK (CLK) transcriptional activity. Here we show that CK2 also targets the CLK activator directly. Downregulating the activity of the catalytic alpha subunit of CK2 induces CLK degradation, even in the absence of PER and TIM. Unexpectedly, the regulatory beta subunit of the CK2 holoenzyme is not required for the regulation of CLK stability. In addition, downregulation of \(CK2\alpha\) activity decreases CLK phosphorylation and increases per and tim transcription. These results indicate that CK2 inhibits CLK degradation while reducing its activity. Since the CK1 kinase promotes CLK degradation, we suggest that CLK stability and transcriptional activity result from counteracting effects of CK1 and CK2. KW - negative feedback loop KW - PER-TIM complex KW - posttranslational regulation KW - transcription factor KW - in-vivo KW - behavioral rhythms KW - proteins period KW - beta-subunit KW - phosphorylation KW - gene KW - CT, circadian time KW - LD, light:dark KW - DD, constant darkness Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-127234 SN - 1545-7885 VL - 11 IS - 8 ER - TY - JOUR A1 - van Dinther, Maarten A1 - Zhang, Juan A1 - Weidauer, Stella E. A1 - Boschert, Verena A1 - Muth, Eva-Maria A1 - Knappik, Achim A1 - de Gorter, David J. J. A1 - van Kasteren, Puck B. A1 - Frisch, Christian A1 - Müller, Thomas D. A1 - ten Dijke, Peter T1 - Anti-Sclerostin Antibody Inhibits Internalization of Sclerostin and Sclerostin-Mediated Antagonism of Wnt/LRP6 Signaling JF - PLoS ONE N2 - Sclerosteosis is a rare high bone mass disease that is caused by inactivating mutations in the SOST gene. Its gene product, Sclerostin, is a key negative regulator of bone formation and might therefore serve as a target for the anabolic treatment of osteoporosis. The exact molecular mechanism by which Sclerostin exerts its antagonistic effects on Wnt signaling in bone forming osteoblasts remains unclear. Here we show that Wnt3a-induced transcriptional responses and induction of alkaline phosphatase activity, an early marker of osteoblast differentiation, require the Wnt co-receptors LRP5 and LRP6. Unlike Dickkopf1 (DKK1), Sclerostin does not inhibit Wnt-3a-induced phosphorylation of LRP5 at serine 1503 or LRP6 at serine 1490. Affinity labeling of cell surface proteins with \([^{125} I]\) Sclerostin identified LRP6 as the main specific Sclerostin receptor in multiple mesenchymal cell lines. When cells were challenged with Sclerostin fused to recombinant green fluorescent protein (GFP) this was internalized, likely via a Clathrin-dependent process, and subsequently degraded in a temperature and proteasome-dependent manner. Ectopic expression of LRP6 greatly enhanced binding and cellular uptake of Sclerostin-GFP, which was reduced by the addition of an excess of non-GFP-fused Sclerostin. Finally, an anti-Sclerostin antibody inhibited the internalization of Sclerostin-GFP and binding of Sclerostin to LRP6. Moreover, this antibody attenuated the antagonistic activity of Sclerostin on canonical Wnt-induced responses. KW - gene KW - rat model KW - Dickkopf proteins KW - postmenopausal osteoporosis KW - increases bone-formation KW - WNT KW - LRP6 KW - density KW - receptor KW - ligand Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-130981 VL - 8 IS - 4 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 -