@article{StoppePatelZarbocketal.2023, author = {Stoppe, Christian and Patel, Jayshil J. and Zarbock, Alex and Lee, Zheng-Yii and Rice, Todd W. and Mafrici, Bruno and Wehner, Rebecca and Chan, Man Hung Manuel and Lai, Peter Chi Keung and MacEachern, Kristen and Myrianthefs, Pavlos and Tsigou, Evdoxia and Ortiz-Reyes, Luis and Jiang, Xuran and Day, Andrew G. and Hasan, M. Shahnaz and Meybohm, Patrick and Ke, Lu and Heyland, Daren K.}, title = {The impact of higher protein dosing on outcomes in critically ill patients with acute kidney injury: a post hoc analysis of the EFFORT protein trial}, series = {Critical Care}, volume = {27}, journal = {Critical Care}, doi = {10.1186/s13054-023-04663-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-357221}, year = {2023}, abstract = {Background Based on low-quality evidence, current nutrition guidelines recommend the delivery of high-dose protein in critically ill patients. The EFFORT Protein trial showed that higher protein dose is not associated with improved outcomes, whereas the effects in critically ill patients who developed acute kidney injury (AKI) need further evaluation. The overall aim is to evaluate the effects of high-dose protein in critically ill patients who developed different stages of AKI. Methods In this post hoc analysis of the EFFORT Protein trial, we investigated the effect of high versus usual protein dose (≥ 2.2 vs. ≤ 1.2 g/kg body weight/day) on time-to-discharge alive from the hospital (TTDA) and 60-day mortality and in different subgroups in critically ill patients with AKI as defined by the Kidney Disease Improving Global Outcomes (KDIGO) criteria within 7 days of ICU admission. The associations of protein dose with incidence and duration of kidney replacement therapy (KRT) were also investigated. Results Of the 1329 randomized patients, 312 developed AKI and were included in this analysis (163 in the high and 149 in the usual protein dose group). High protein was associated with a slower time-to-discharge alive from the hospital (TTDA) (hazard ratio 0.5, 95\% CI 0.4-0.8) and higher 60-day mortality (relative risk 1.4 (95\% CI 1.1-1.8). Effect modification was not statistically significant for any subgroup, and no subgroups suggested a beneficial effect of higher protein, although the harmful effect of higher protein target appeared to disappear in patients who received kidney replacement therapy (KRT). Protein dose was not significantly associated with the incidence of AKI and KRT or duration of KRT. Conclusions In critically ill patients with AKI, high protein may be associated with worse outcomes in all AKI stages. Recommendation of higher protein dosing in AKI patients should be carefully re-evaluated to avoid potential harmful effects especially in patients who were not treated with KRT. Trial registration: This study is registered at ClinicalTrials.gov (NCT03160547) on May 17th 2017.}, language = {en} } @article{FeldheimKesslerFeldheimetal.2023, author = {Feldheim, Jonas and Kessler, Almuth F. and Feldheim, Julia J. and Schmitt, Dominik and Oster, Christoph and Lazaridis, Lazaros and Glas, Martin and Ernestus, Ralf-Ingo and Monoranu, Camelia M. and L{\"o}hr, Mario and Hagemann, Carsten}, title = {BRMS1 in gliomas — an expression analysis}, series = {Cancers}, volume = {15}, journal = {Cancers}, number = {11}, issn = {2072-6694}, doi = {10.3390/cancers15112907}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-319225}, year = {2023}, abstract = {The metastatic suppressor BRMS1 interacts with critical steps of the metastatic cascade in many cancer entities. As gliomas rarely metastasize, BRMS1 has mainly been neglected in glioma research. However, its interaction partners, such as NFκB, VEGF, or MMPs, are old acquaintances in neurooncology. The steps regulated by BRMS1, such as invasion, migration, and apoptosis, are commonly dysregulated in gliomas. Therefore, BRMS1 shows potential as a regulator of glioma behavior. By bioinformatic analysis, in addition to our cohort of 118 specimens, we determined BRMS1 mRNA and protein expression as well as its correlation with the clinical course in astrocytomas IDH mutant, CNS WHO grade 2/3, and glioblastoma IDH wild-type, CNS WHO grade 4. Interestingly, we found BRMS1 protein expression to be significantly decreased in the aforementioned gliomas, while BRMS1 mRNA appeared to be overexpressed throughout. This dysregulation was independent of patients' characteristics or survival. The protein and mRNA expression differences cannot be finally explained at this stage. However, they suggest a post-transcriptional dysregulation that has been previously described in other cancer entities. Our analyses present the first data on BRMS1 expression in gliomas that can provide a starting point for further investigations.}, language = {en} } @article{FeldheimWendLaueretal.2022, author = {Feldheim, Jonas and Wend, David and Lauer, Mara J. and Monoranu, Camelia M. and Glas, Martin and Kleinschnitz, Christoph and Ernestus, Ralf-Ingo and Braunger, Barbara M. and Meybohm, Patrick and Hagemann, Carsten and Burek, Malgorzata}, title = {Protocadherin Gamma C3 (PCDHGC3) is strongly expressed in glioblastoma and its high expression is associated with longer progression-free survival of patients}, series = {International Journal of Molecular Sciences}, volume = {23}, journal = {International Journal of Molecular Sciences}, number = {15}, issn = {1422-0067}, doi = {10.3390/ijms23158101}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-284433}, year = {2022}, abstract = {Protocadherins (PCDHs) belong to the cadherin superfamily and represent the largest subgroup of calcium-dependent adhesion molecules. In the genome, most PCDHs are arranged in three clusters, α, β, and γ on chromosome 5q31. PCDHs are highly expressed in the central nervous system (CNS). Several PCDHs have tumor suppressor functions, but their individual role in primary brain tumors has not yet been elucidated. Here, we examined the mRNA expression of PCDHGC3, a member of the PCDHγ cluster, in non-cancerous brain tissue and in gliomas of different World Health Organization (WHO) grades and correlated it with the clinical data of the patients. We generated a PCDHGC3 knockout U343 cell line and examined its growth rate and migration in a wound healing assay. We showed that PCDHGC3 mRNA and protein were significantly overexpressed in glioma tissue compared to a non-cancerous brain specimen. This could be confirmed in glioma cell lines. High PCDHGC3 mRNA expression correlated with longer progression-free survival (PFS) in glioma patients. PCDHGC3 knockout in U343 resulted in a slower growth rate but a significantly faster migration rate in the wound healing assay and decreased the expression of several genes involved in WNT signaling. PCDHGC3 expression should therefore be further investigated as a PFS-marker in gliomas. However, more studies are needed to elucidate the molecular mechanisms underlying the PCDHGC3 effects.}, language = {en} } @article{ElMoualiGerovacMineikaitėetal.2021, author = {El Mouali, Youssef and Gerovac, Milan and Mineikaitė, Raminta and Vogel, J{\"o}rg}, title = {In vivo targets of Salmonella FinO include a FinP-like small RNA controlling copy number of a cohabitating plasmid}, series = {Nucleic Acids Research}, volume = {49}, journal = {Nucleic Acids Research}, number = {9}, doi = {10.1093/nar/gkab281}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-261072}, pages = {5319-5335}, year = {2021}, abstract = {FinO-domain proteins represent an emerging family of RNA-binding proteins (RBPs) with diverse roles in bacterial post-transcriptional control and physiology. They exhibit an intriguing targeting spectrum, ranging from an assumed single RNA pair (FinP/traJ) for the plasmid-encoded FinO protein, to transcriptome-wide activity as documented for chromosomally encoded ProQ proteins. Thus, the shared FinO domain might bear an unusual plasticity enabling it to act either selectively or promiscuously on the same cellular RNA pool. One caveat to this model is that the full suite of in vivo targets of the assumedly highly selective FinO protein is unknown. Here, we have extensively profiled cellular transcripts associated with the virulence plasmid-encoded FinO in Salmonella enterica. While our analysis confirms the FinP sRNA of plasmid pSLT as the primary FinO target, we identify a second major ligand: the RepX sRNA of the unrelated antibiotic resistance plasmid pRSF1010. FinP and RepX are strikingly similar in length and structure, but not in primary sequence, and so may provide clues to understanding the high selectivity of FinO-RNA interactions. Moreover, we observe that the FinO RBP encoded on the Salmonella virulence plasmid controls the replication of a cohabitating antibiotic resistance plasmid, suggesting cross-regulation of plasmids on the RNA level.}, language = {en} } @article{TolayBuchberger2021, author = {Tolay, Nazife and Buchberger, Alexander}, title = {Comparative profiling of stress granule clearance reveals differential contributions of the ubiquitin system}, series = {Life Science Alliance}, volume = {4}, journal = {Life Science Alliance}, number = {5}, doi = {10.26508/lsa.202000927}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259810}, pages = {e202000927}, year = {2021}, abstract = {Stress granules (SGs) are cytoplasmic condensates containing untranslated mRNP complexes. They are induced by various proteotoxic conditions such as heat, oxidative, and osmotic stress. SGs are believed to protect mRNPs from degradation and to enable cells to rapidly resume translation when stress conditions subside. SG dynamics are controlled by various posttranslationalmodifications, but the role of the ubiquitin system has remained controversial. Here, we present a comparative analysis addressing the involvement of the ubiquitin system in SG clearance. Using high-resolution immuno-fluorescence microscopy, we found that ubiquitin associated to varying extent with SGs induced by heat, arsenite, H2O2, sorbitol, or combined puromycin and Hsp70 inhibitor treatment. SG-associated ubiquitin species included K48- and K63-linked conjugates, whereas free ubiquitin was not significantly enriched. Inhibition of the ubiquitin activating enzyme, deubiquitylating enzymes, the 26S proteasome and p97/VCP impaired the clearance of arsenite- and heat-induced SGs, whereas SGs induced by other stress conditions were little affected. Our data underline the differential involvement of the ubiquitin system in SG clearance, a process important to prevent the formation of disease-linked aberrant SGs.}, language = {en} } @article{FeldheimKesslerSchmittetal.2020, author = {Feldheim, Jonas and Kessler, Almuth F. and Schmitt, Dominik and Salvador, Ellaine and Monoranu, Camelia M. and Feldheim, Julia J. and Ernestus, Ralf-Ingo and L{\"o}hr, Mario and Hagemann, Carsten}, title = {Ribosomal Protein S27/Metallopanstimulin-1 (RPS27) in Glioma — A New Disease Biomarker?}, series = {Cancers}, volume = {12}, journal = {Cancers}, number = {5}, issn = {2072-6694}, doi = {10.3390/cancers12051085}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-203648}, year = {2020}, abstract = {Despite its significant overexpression in several malignant neoplasms, the expression of RPS27 in the central nervous system (CNS) is widely unknown. We identified the cell types expressing RPS27 in the CNS under normal and disease conditions. We acquired specimens of healthy brain (NB), adult pilocytic astrocytoma (PA) World Health Organization (WHO) grade I, anaplastic PA WHO grade III, gliomas WHO grade II/III with or without isocitrate dehydrogenase (IDH) mutation, and glioblastoma multiforme (GBM). RPS27 protein expression was examined by immunohistochemistry and double-fluorescence staining and its mRNA expression quantified by RT-PCR. Patients' clinical and tumor characteristics were collected retrospectively. RPS27 protein was specifically expressed in tumor cells and neurons, but not in healthy astrocytes. In tumor tissue, most macrophages were positive, while this was rarely the case in inflamed tissue. Compared to NB, RPS27 mRNA was in mean 6.2- and 8.8-fold enhanced in gliomas WHO grade II/III with (p < 0.01) and without IDH mutation (p = 0.01), respectively. GBM displayed a 4.6-fold increased mean expression (p = 0.02). Although RPS27 expression levels did not affect the patients' survival, their association with tumor cells and tumor-associated macrophages provides a rationale for a future investigation of a potential function during gliomagenesis and tumor immune response.}, language = {en} } @article{HoffmannSchmidtKeimetal.2011, author = {Hoffmann, Linda S and Schmidt, Peter M and Keim, Yvonne and Hoffmann, Carsten and Schmidt, Harald H H W and Stasch, Johannes-Peter}, title = {Fluorescence Dequenching Makes Haem-Free Soluble Guanylate Cyclase Detectable in Living Cells}, series = {PLOS ONE}, volume = {6}, journal = {PLOS ONE}, number = {8}, doi = {10.1371/journal.pone.0023596}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-139631}, pages = {e23596}, year = {2011}, abstract = {In cardiovascular disease, the protective NO/sGC/cGMP signalling-pathway is impaired due to a decreased pool of NO-sensitive haem-containing sGC accompanied by a reciprocal increase in NO-insensitive haem-free sGC. However, no direct method to detect cellular haem-free sGC other than its activation by the new therapeutic class of haem mimetics, such as BAY 58-2667, is available. Here we show that fluorescence dequenching, based on the interaction of the optical active prosthetic haem group and the attached biarsenical fluorophor FlAsH can be used to detect changes in cellular sGC haem status. The partly overlap of the emission spectrum of haem and FlAsH allows energy transfer from the fluorophore to the haem which reduces the intensity of FlAsH fluorescence. Loss of the prosthetic group, e. g. by oxidative stress or by replacement with the haem mimetic BAY 58-2667, prevented the energy transfer resulting in increased fluorescence. Haem loss was corroborated by an observed decrease in NO-induced sGC activity, reduced sGC protein levels, and an increased effect of BAY 58-2667. The use of a haem-free sGC mutant and a biarsenical dye that was not quenched by haem as controls further validated that the increase in fluorescence was due to the loss of the prosthetic haem group. The present approach is based on the cellular expression of an engineered sGC variant limiting is applicability to recombinant expression systems. Nevertheless, it allows to monitor sGC's redox regulation in living cells and future enhancements might be able to extend this approach to in vivo conditions.}, language = {en} } @article{ZanuccoGoetzPotapenkoetal.2011, author = {Zanucco, Emanuele and G{\"o}tz, Rudolf and Potapenko, Tamara and Carraretto, Irene and Ceteci, Semra and Ceteci, Fatih and Seeger, Werner and Savai, Rajkumar and Rapp, Ulf R.}, title = {Expression of B-RAF V600E in Type II Pneumocytes Causes Abnormalities in Alveolar Formation, Airspace Enlargement and Tumor Formation in Mice}, series = {PLOS ONE}, volume = {6}, journal = {PLOS ONE}, number = {12}, doi = {10.1371/journal.pone.0029093}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-137061}, pages = {e29093}, year = {2011}, abstract = {Growth factor induced signaling cascades are key regulatory elements in tissue development, maintenance and regeneration. Perturbations of these cascades have severe consequences, leading to developmental disorders and neoplastic diseases. As a major function in signal transduction, activating mutations in RAF family kinases are the cause of human tumorigenesis, where B-RAF V600E has been identified as the prevalent mutant. In order to address the oncogenic function of B-RAF V600E, we have generated transgenic mice expressing the activated oncogene specifically in lung alveolar epithelial type II cells. Constitutive expression of B-RAF V600E caused abnormalities in alveolar epithelium formation that led to airspace enlargements. These lung lesions showed signs of tissue remodeling and were often associated with chronic inflammation and low incidence of lung tumors. The inflammatory cell infiltration did not precede the formation of the lung lesions but was rather accompanied with late tumor development. These data support a model where the continuous regenerative process initiated by oncogenic B-RAF-driven alveolar disruption provides a tumor-promoting environment associated with chronic inflammation.}, language = {en} } @article{HarringtonScelsiHarteletal.2012, author = {Harrington, John M. and Scelsi, Chris and Hartel, Andreas and Jones, Nicola G. and Engstler, Markus and Capewell, Paul and MacLeod, Annette and Hajduk, Stephen}, title = {Novel African Trypanocidal Agents: Membrane Rigidifying Peptides}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {9}, doi = {10.1371/journal.pone.0044384}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-135179}, pages = {e44384}, year = {2012}, abstract = {The bloodstream developmental forms of pathogenic African trypanosomes are uniquely susceptible to killing by small hydrophobic peptides. Trypanocidal activity is conferred by peptide hydrophobicity and charge distribution and results from increased rigidity of the plasma membrane. Structural analysis of lipid-associated peptide suggests a mechanism of phospholipid clamping in which an internal hydrophobic bulge anchors the peptide in the membrane and positively charged moieties at the termini coordinate phosphates of the polar lipid headgroups. This mechanism reveals a necessary phenotype in bloodstream form African trypanosomes, high membrane fluidity, and we suggest that targeting the plasma membrane lipid bilayer as a whole may be a novel strategy for the development of new pharmaceutical agents. Additionally, the peptides we have described may be valuable tools for probing the biosynthetic machinery responsible for the unique composition and characteristics of African trypanosome plasma membranes.}, language = {en} } @article{WorkuStichDaugschiesetal.2015, author = {Worku, Netsanet and Stich, August and Daugschies, Arwid and Wenzel, Iris and Kurz, Randy and Thieme, Rene and Kurz, Susanne and Birkenmeier, Gerd}, title = {Ethyl Pyruvate Emerges as a Safe and Fast Acting Agent against Trypanosoma brucei by Targeting Pyruvate Kinase Activity}, series = {PLoS ONE}, volume = {10}, journal = {PLoS ONE}, number = {9}, doi = {10.1371/journal.pone.0137353}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-150002}, pages = {e0137353}, year = {2015}, abstract = {Background Human African Trypanosomiasis (HAT) also called sleeping sickness is an infectious disease in humans caused by an extracellular protozoan parasite. The disease, if left untreated, results in 100\% mortality. Currently available drugs are full of severe drawbacks and fail to escape the fast development of trypanosoma resistance. Due to similarities in cell metabolism between cancerous tumors and trypanosoma cells, some of the current registered drugs against HAT have also been tested in cancer chemotherapy. Here we demonstrate for the first time that the simple ester, ethyl pyruvate, comprises such properties. Results The current study covers the efficacy and corresponding target evaluation of ethyl pyruvate on T. brucei cell lines using a combination of biochemical techniques including cell proliferation assays, enzyme kinetics, phasecontrast microscopic video imaging and ex vivo toxicity tests. We have shown that ethyl pyruvate effectively kills trypanosomes most probably by net ATP depletion through inhibition of pyruvate kinase (Ki = 3.0\(\pm\)0.29 mM). The potential of ethyl pyruvate as a trypanocidal compound is also strengthened by its fast acting property, killing cells within three hours post exposure. This has been demonstrated using video imaging of live cells as well as concentration and time dependency experiments. Most importantly, ethyl pyruvate produces minimal side effects in human red cells and is known to easily cross the blood-brain-barrier. This makes it a promising candidate for effective treatment of the two clinical stages of sleeping sickness. Trypanosome drug-resistance tests indicate irreversible cell death and a low incidence of resistance development under experimental conditions. Conclusion Our results present ethyl pyruvate as a safe and fast acting trypanocidal compound and show that it inhibits the enzyme pyruvate kinase. Competitive inhibition of this enzyme was found to cause ATP depletion and cell death. Due to its ability to easily cross the blood-brain-barrier, ethyl pyruvate could be considered as new candidate agent to treat the hemo-lymphatic as well as neurological stages of sleeping sickness.}, language = {en} } @article{VieiraJonesDanonetal.2012, author = {Vieira, Jacqueline and Jones, Alex R. and Danon, Antoine and Sakuma, Michiyo and Hoang, Nathalie and Robles, David and Tait, Shirley and Heyes, Derren J. and Picot, Marie and Yoshii, Taishi and Helfrich-F{\"o}rster, Charlotte and Soubigou, Guillaume and Coppee, Jean-Yves and Klarsfeld, Andr{\´e} and Rouyer, Francois and Scrutton, Nigel S. and Ahmad, Margaret}, title = {Human Cryptochrome-1 Confers Light Independent Biological Activity in Transgenic Drosophila Correlated with Flavin Radical Stability}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {3}, doi = {10.1371/journal.pone.0031867}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-134513}, pages = {e31867}, year = {2012}, abstract = {Cryptochromes are conserved flavoprotein receptors found throughout the biological kingdom with diversified roles in plant development and entrainment of the circadian clock in animals. Light perception is proposed to occur through flavin radical formation that correlates with biological activity in vivo in both plants and Drosophila. By contrast, mammalian (Type II) cryptochromes regulate the circadian clock independently of light, raising the fundamental question of whether mammalian cryptochromes have evolved entirely distinct signaling mechanisms. Here we show by developmental and transcriptome analysis that Homo sapiens cryptochrome - 1 (HsCRY1) confers biological activity in transgenic expressing Drosophila in darkness, that can in some cases be further stimulated by light. In contrast to all other cryptochromes, purified recombinant HsCRY1 protein was stably isolated in the anionic radical flavin state, containing only a small proportion of oxidized flavin which could be reduced by illumination. We conclude that animal Type I and Type II cryptochromes may both have signaling mechanisms involving formation of a flavin radical signaling state, and that light independent activity of Type II cryptochromes is a consequence of dark accumulation of this redox form in vivo rather than of a fundamental difference in signaling mechanism.}, language = {en} } @article{MolochnikovRabeyDobronevskyetal.2012, author = {Molochnikov, Leonid and Rabey, Jose M. and Dobronevsky, Evgenya and Bonuccelli, Ubaldo and Ceravolo, Roberto and Frosini, Daniela and Gr{\"u}nblatt, Edna and Riederer, Peter and Jacob, Christian and Aharon-Peretz, Judith and Bashenko, Yulia and Youdim, Moussa B. H. and Mandel, Silvia A.}, title = {A molecular signature in blood identifies early Parkinson's disease}, series = {Molecular Neurodegeneration}, volume = {7}, journal = {Molecular Neurodegeneration}, number = {26}, doi = {10.1186/1750-1326-7-26}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-134508}, year = {2012}, abstract = {Background: The search for biomarkers in Parkinson's disease (PD) is crucial to identify the disease early and monitor the effectiveness of neuroprotective therapies. We aim to assess whether a gene signature could be detected in blood from early/mild PD patients that could support the diagnosis of early PD, focusing on genes found particularly altered in the substantia nigra of sporadic PD. Results: The transcriptional expression of seven selected genes was examined in blood samples from 62 early stage PD patients and 64 healthy age-matched controls. Stepwise multivariate logistic regression analysis identified five genes as optimal predictors of PD: p19 S-phase kinase-associated protein 1A (odds ratio [OR] 0.73; 95\% confidence interval [CI] 0.60-0.90), huntingtin interacting protein-2 (OR 1.32; CI 1.08-1.61), aldehyde dehydrogenase family 1 subfamily A1 (OR 0.86; 95\% CI 0.75-0.99), 19 S proteasomal protein PSMC4 (OR 0.73; 95\% CI 0.60-0.89) and heat shock 70-kDa protein 8 (OR 1.39; 95\% CI 1.14-1.70). At a 0.5 cut-off the gene panel yielded a sensitivity and specificity in detecting PD of 90.3 and 89.1 respectively and the area under the receiving operating curve (ROC AUC) was 0.96. The performance of the five-gene classifier on the de novo PD individuals alone composing the early PD cohort (n = 38), resulted in a similar ROC with an AUC of 0.95, indicating the stability of the model and also, that patient medication had no significant effect on the predictive probability (PP) of the classifier for PD risk. The predictive ability of the model was validated in an independent cohort of 30 patients at advanced stage of PD, classifying correctly all cases as PD (100\% sensitivity). Notably, the nominal average value of the PP for PD (0.95 (SD = 0.09)) in this cohort was higher than that of the early PD group (0.83 (SD = 0.22)), suggesting a potential for the model to assess disease severity. Lastly, the gene panel fully discriminated between PD and Alzheimer's disease (n = 29). Conclusions: The findings provide evidence on the ability of a five-gene panel to diagnose early/mild PD, with a possible diagnostic value for detection of asymptomatic PD before overt expression of the disorder.}, language = {en} } @article{TessmerMelikishviliFried2012, author = {Tessmer, Ingrid and Melikishvili, Manana and Fried, Michael G.}, title = {Cooperative cluster formation, DNA bending and base-flipping by O\(^6\)-alkylguanine-DNA alkyltransferase}, series = {Nucleic Acids Research}, volume = {40}, journal = {Nucleic Acids Research}, number = {17}, doi = {10.1093/nar/gks574}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133949}, pages = {8296-8308}, year = {2012}, abstract = {O\(^6\)-Alkylguanine-DNA alkyltransferase (AGT) repairs mutagenic O\(^6\)-alkylguanine and O\(^4\)-alkylthymine adducts in DNA, protecting the genome and also contributing to the resistance of tumors to chemotherapeutic alkylating agents. AGT binds DNA cooperatively, and cooperative interactions are likely to be important in lesion search and repair. We examined morphologies of complexes on long, unmodified DNAs, using analytical ultracentrifugation and atomic force microscopy. AGT formed clusters of 11 proteins. Longer clusters, predicted by the McGhee-von Hippel model, were not seen even at high [protein]. Interestingly, torsional stress due to DNA unwinding has the potential to limit cluster size to the observed range. DNA at cluster sites showed bend angles (similar to 0, similar to 30 and similar to 60 degrees) that are consistent with models in which each protein induces a bend of similar to 30 degrees. Distributions of complexes along the DNA are incompatible with sequence specificity but suggest modest preference for DNA ends. These properties tell us about environments in which AGT may function. Small cooperative clusters and the ability to accommodate a range of DNA bends allow function where DNA topology is constrained, such as near DNA-replication complexes. The low sequence specificity allows efficient and unbiased lesion search across the entire genome.}, language = {en} } @article{FernandezRodriguezQuilesBlancoetal.2012, author = {Fern{\´a}ndez-Rodr{\´i}guez, Juana and Quiles, Francisco and Blanco, Ignacio and Teul{\´e}, Alex and Feliubadal{\´o}, L{\´i}dia and del Valle, Jes{\´u}s and Salinas, M{\´o}nica and Izquierdo, {\´A}ngel and Darder, Esther and Schindler, Detlev and Capell{\´a}, Gabriel and Brunet, Joan and L{\´a}zaro, Conxi and Angel Pujana, Miguel}, title = {Analysis of SLX4/FANCP in non-BRCA1/2-mutated breast cancer families}, series = {BMC Cancer}, volume = {12}, journal = {BMC Cancer}, number = {84}, doi = {10.1186/1471-2407-12-84}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131772}, year = {2012}, abstract = {Background: Genes that, when mutated, cause Fanconi anemia or greatly increase breast cancer risk encode for proteins that converge on a homology-directed DNA damage repair process. Mutations in the SLX4 gene, which encodes for a scaffold protein involved in the repair of interstrand cross-links, have recently been identified in unclassified Fanconi anemia patients. A mutation analysis of SLX4 in German or Byelorussian familial cases of breast cancer without detected mutations in BRCA1 or BRCA2 has been completed, with globally negative results. Methods: The genomic region of SLX4, comprising all exons and exon-intron boundaries, was sequenced in 94 Spanish familial breast cancer cases that match a criterion indicating the potential presence of a highly-penetrant germline mutation, following exclusion of BRCA1 or BRCA2 mutations. Results: This mutational analysis revealed extensive genetic variation of SLX4, with 21 novel single nucleotide variants; however, none could be linked to a clear alteration of the protein function. Nonetheless, genotyping 10 variants (nine novel, all missense amino acid changes) in a set of controls (138 women and 146 men) did not detect seven of them. Conclusions: Overall, while the results of this study do not identify clearly pathogenic mutations of SLX4 contributing to breast cancer risk, further genetic analysis, combined with functional assays of the identified rare variants, may be warranted to conclusively assess the potential link with the disease.}, language = {en} } @article{GassenBrechtefeldSchandryetal.2012, author = {Gassen, Alwine and Brechtefeld, Doris and Schandry, Niklas and Arteaga-Salas, J. Manuel and Israel, Lars and Imhof, Axel and Janzen, Christian J.}, title = {DOT1A-dependent H3K76 methylation is required for replication regulation in Trypanosoma brucei}, series = {Nucleic Acids Research}, volume = {40}, journal = {Nucleic Acids Research}, number = {20}, doi = {10.1093/nar/gks801}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131449}, pages = {10302 - 10311}, year = {2012}, abstract = {Cell-cycle progression requires careful regulation to ensure accurate propagation of genetic material to the daughter cells. Although many cell-cycle regulators are evolutionarily conserved in the protozoan parasite Trypanosoma brucei, novel regulatory mechanisms seem to have evolved. Here, we analyse the function of the histone methyltransferase DOT1A during cell-cycle progression. Over-expression of DOT1A generates a population of cells with aneuploid nuclei as well as enucleated cells. Detailed analysis shows that DOT1A over-expression causes continuous replication of the nuclear DNA. In contrast, depletion of DOT1A by RNAi abolishes replication but does not prevent karyokinesis. As histone H3K76 methylation has never been associated with replication control in eukaryotes before, we have discovered a novel function of DOT1 enzymes, which might not be unique to trypanosomes.}, language = {en} } @article{BugaScholzKumaretal.2012, author = {Buga, Ana-Maria and Scholz, Claus J{\"u}rgen and Kumar, Senthil and Herndon, James G. and Alexandru, Dragos and Cojocaru, Gabriel Radu and Dandekar, Thomas and Popa-Wagner, Aurel}, title = {Identification of New Therapeutic Targets by Genome-Wide Analysis of Gene Expression in the Ipsilateral Cortex of Aged Rats after Stroke}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {12}, doi = {10.1371/journal.pone.0050985}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-130657}, pages = {e50985}, year = {2012}, abstract = {Background: Because most human stroke victims are elderly, studies of experimental stroke in the aged rather than the young rat model may be optimal for identifying clinically relevant cellular responses, as well for pinpointing beneficial interventions. Methodology/Principal Findings: We employed the Affymetrix platform to analyze the whole-gene transcriptome following temporary ligation of the middle cerebral artery in aged and young rats. The correspondence, heat map, and dendrogram analyses independently suggest a differential, age-group-specific behaviour of major gene clusters after stroke. Overall, the pattern of gene expression strongly suggests that the response of the aged rat brain is qualitatively rather than quantitatively different from the young, i.e. the total number of regulated genes is comparable in the two age groups, but the aged rats had great difficulty in mounting a timely response to stroke. Our study indicates that four genes related to neuropathic syndrome, stress, anxiety disorders and depression (Acvr1c, Cort, Htr2b and Pnoc) may have impaired response to stroke in aged rats. New therapeutic options in aged rats may also include Calcrl, Cyp11b1, Prcp, Cebpa, Cfd, Gpnmb, Fcgr2b, Fcgr3a, Tnfrsf26, Adam 17 and Mmp14. An unexpected target is the enzyme 3-hydroxy-3-methylglutaryl-Coenzyme A synthase 1 in aged rats, a key enzyme in the cholesterol synthesis pathway. Post-stroke axonal growth was compromised in both age groups. Conclusion/Significance: We suggest that a multi-stage, multimodal treatment in aged animals may be more likely to produce positive results. Such a therapeutic approach should be focused on tissue restoration but should also address other aspects of patient post-stroke therapy such as neuropathic syndrome, stress, anxiety disorders, depression, neurotransmission and blood pressure.}, language = {en} } @article{StepniakKaestnerPoggietal.2015, author = {Stepniak, Beata and K{\"a}stner, Anne and Poggi, Giulia and Mitjans, Marina and Begemann, Martin and Hartmann, Annette and Van der Auwera, Sandra and Sananbenesi, Farahnaz and Kr{\"u}ger-Burg, Dilja and Matuszko, Gabriela and Brosi, Cornelia and Homuth, Georg and V{\"o}lzke, Henry and Benseler, Fritz and Bagni, Claudia and Fischer, Utz and Dityatev, Alexander and Grabe, Hans-J{\"o}rgen and Rujescu, Dan and Fischer, Andre and Ehrenreich, Hannelore}, title = {Accumulated common variants in the broader fragile X gene family modulate autistic phenotypes}, series = {EMBO Molecular Medicine}, volume = {7}, journal = {EMBO Molecular Medicine}, number = {12}, doi = {10.15252/emmm.201505696}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-136893}, pages = {1565-1579}, year = {2015}, abstract = {Fragile X syndrome (FXS) is mostly caused by a CGG triplet expansion in the fragile X mental retardation 1 gene (FMR1). Up to 60\% of affected males fulfill criteria for autism spectrum disorder (ASD), making FXS the most frequent monogenetic cause of syndromic ASD. It is unknown, however, whether normal variants (independent of mutations) in the fragile X gene family (FMR1, FXR1, FXR2) and in FMR2 modulate autistic features. Here, we report an accumulation model of 8 SNPs in these genes, associated with autistic traits in a discovery sample of male patients with schizophrenia (N = 692) and three independent replicate samples: patients with schizophrenia (N = 626), patients with other psychiatric diagnoses (N = 111) and a general population sample (N = 2005). For first mechanistic insight, we contrasted microRNA expression in peripheral blood mononuclear cells of selected extreme group subjects with high-versus low-risk constellation regarding the accumulation model. Thereby, the brain-expressed miR-181 species emerged as potential "umbrella regulator", with several seed matches across the fragile X gene family and FMR2. To conclude, normal variation in these genes contributes to the continuum of autistic phenotypes.}, language = {en} } @article{RodriguesPopovKayeetal.2013, author = {Rodrigues, L{\´e}nia and Popov, Nikita and Kaye, Kenneth M. and Simas, J. Pedro}, title = {Stabilization of Myc through Heterotypic Poly-Ubiquitination by mLANA Is Critical for \(\gamma\)-Herpesvirus Lymphoproliferation}, series = {PLoS PATHOGENS}, volume = {9}, journal = {PLoS PATHOGENS}, number = {8}, doi = {10.1371/journal.ppat.1003554}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131227}, pages = {e1003554}, year = {2013}, abstract = {Host colonization by lymphotropic \(\gamma\)-herpesviruses depends critically on expansion of viral genomes in germinal center (GC) B-cells. Myc is essential for the formation and maintenance of GCs. Yet, the role of Myc in the pathogenesis of \(\gamma\)-cherpesviruses is still largely unknown. In this study, Myc was shown to be essential for the lymphotropic \(\gamma\)-herpesvirus MuHV- 4 biology as infected cells exhibited increased expression of Myc signature genes and the virus was unable to expand in Myc defficient GC B- cells. We describe a novel strategy of a viral protein activating Myc through increased protein stability resulting in increased progression through the cell cycle. This is acomplished by modulating a physiological posttranslational regulatory pathway of Myc. The molecular mechanism involves Myc heterotypic poly- ubiquitination mediated via the viral E3 ubiquitin- ligase mLANA protein. \(EC_5S^{mLANA}\) modulates cellular control of Myc turnover by antagonizing \(SCF^{Fbw7}\) mediated proteasomal degradation of Myc, mimicking \(SCF^{\beta-TrCP}\). The findings here reported reveal that modulation of Myc is essential for \(\gamma\)-herpesvirus persistent infection, establishing a link between virus induced lymphoproliferation and disease.}, language = {en} } @article{KarleSchueleKlebeetal.2013, author = {Karle, Kathrin N. and Sch{\"u}le, Rebecca and Klebe, Stephan and Otto, Susanne and Frischholz, Christian and Liepelt-Scarfone, Inga and Sch{\"o}ls, Ludger}, title = {Electrophysiological characterisation of motor and sensory tracts in patients with hereditary spastic paraplegia (HSP)}, series = {Orphanet Journal of Rare Diseases}, volume = {8}, journal = {Orphanet Journal of Rare Diseases}, number = {158}, issn = {1750-1172}, doi = {10.1186/1750-1172-8-158}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-124763}, year = {2013}, abstract = {Background: Hereditary spastic paraplegias (HSPs) are characterised by lower limb spasticity due to degeneration of the corticospinal tract. We set out for an electrophysiological characterisation of motor and sensory tracts in patients with HSP. Methods: We clinically and electrophysiologically examined a cohort of 128 patients with genetically confirmed or clinically probable HSP. Motor evoked potentials (MEPs) to arms and legs, somato-sensory evoked potentials of median and tibial nerves, and nerve conduction studies of tibial, ulnar, sural, and radial nerves were assessed. Results: Whereas all patients showed clinical signs of spastic paraparesis, MEPs were normal in 27\% of patients and revealed a broad spectrum with axonal or demyelinating features in the others. This heterogeneity can at least in part be explained by different underlying genotypes, hinting for distinct pathomechanisms in HSP subtypes. In the largest subgroup, SPG4, an axonal type of damage was evident. Comprehensive electrophysiological testing disclosed a more widespread affection of long fibre tracts involving peripheral nerves and the sensory system in 40\%, respectively. Electrophysiological abnormalities correlated with the severity of clinical symptoms. Conclusions: Whereas HSP is primarily considered as an upper motoneuron disorder, our data suggest a more widespread affection of motor and sensory tracts in the central and peripheral nervous system as a common finding in HSP. The distribution patterns of electrophysiological abnormalities were associated with distinct HSP genotypes and could reflect different underlying pathomechanisms. Electrophysiological measures are independent of symptomatic treatment and may therefore serve as a reliable biomarker in upcoming HSP trials.}, language = {en} } @article{FaragFroehlerOexleetal.2013, author = {Farag, Heba Gamal and Froehler, Sebastian and Oexle, Konrad and Ravindran, Ethiraj and Schindler, Detlev and Staab, Timo and Huebner, Angela and Kraemer, Nadine and Chen, Wei and Kaindl, Angela M.}, title = {Abnormal centrosome and spindle morphology in a patient with autosomal recessive primary microcephaly type 2 due to compound heterozygous WDR62 gene mutation}, series = {Orphanet Journal of Rare Diseases}, volume = {8}, journal = {Orphanet Journal of Rare Diseases}, number = {178}, issn = {1750-1172}, doi = {10.1186/1750-1172-8-178}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-123505}, year = {2013}, abstract = {Background: Autosomal recessive primary microcephaly (MCPH) is a rare neurodevelopmental disease with severe microcephaly at birth due to a pronounced reduction in brain volume and intellectual disability. Biallelic mutations in the WD repeat-containing protein 62 gene WDR62 are the genetic cause of MCPH2. However, the exact underlying pathomechanism of MCPH2 remains to be clarified. Methods/results: We characterized the clinical, radiological, and cellular features that add to the human MCPH2 phenotype. Exome sequencing followed by Sanger sequencing in a German family with two affected daughters with primary microcephaly revealed in the index patient the compound heterozygous mutations c. 1313G>A (p.R438H) / c.2864-2867delACAG (p.D955Afs*112) of WDR62, the second of which is novel. Radiological examination displayed small frontal lobes, corpus callosum hypoplasia, simplified hippocampal gyration, and cerebellar hypoplasia. We investigated the cellular phenotype in patient-derived lymphoblastoid cells and compared it with that of healthy female controls. WDR62 expression in the patient's immortalized lymphocytes was deranged, and mitotic spindle defects as well as abnormal centrosomal protein localization were apparent. Conclusion: We propose that a disruption of centrosome integrity and/or spindle organization may play an important role in the development of microcephaly in MCPH2.}, language = {en} }