@article{LamatschAdolfssonSenioretal.2015, author = {Lamatsch, Dunja K. and Adolfsson, Sofia and Senior, Alistair M. and Christiansen, Guntram and Pichler, Maria and Ozaki, Yuichi and Smeds, Linnea and Schartl, Manfred and Nakagawa, Shinichi}, title = {A transcriptome derived female-specific marker from the invasive Western mosquitofish (Gambusia affinis)}, series = {PLoS ONE}, volume = {10}, journal = {PLoS ONE}, number = {2}, doi = {10.1371/journal.pone.0118214}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-144004}, pages = {e0118214}, year = {2015}, abstract = {Sex-specific markers are a prerequisite for understanding reproductive biology, genetic factors involved in sex differences, mechanisms of sex determination, and ultimately the evolution of sex chromosomes. The Western mosquitofish, Gambusia affinis, may be considered a model species for sex-chromosome evolution, as it displays female heterogamety (ZW/ZZ), and is also ecologically interesting as a worldwide invasive species. Here, de novo RNA-sequencing on the gonads of sexually mature G. affinis was used to identify contigs that were highly transcribed in females but not in males (i.e., transcripts with ovary-specific expression). Subsequently, 129 primer pairs spanning 79 contigs were tested by PCR to identify sex-specific transcripts. Of those primer pairs, one female-specific DNA marker was identified, Sanger sequenced and subsequently validated in 115 fish. Sequence analyses revealed a high similarity between the identified sex-specific marker and the 3' UTR of the aminomethyl transferase (amt) gene of the closely related platyfish (Xiphophorus maculatus). This is the first time that RNA-seq has been used to successfully characterize a sex-specific marker in a fish species in the absence of a genome map. Additionally, the identified sex-specific marker represents one of only a handful of such markers in fishes.}, language = {en} } @article{KangManousakiFranchinietal.2015, author = {Kang, Ji Hyoun and Manousaki, Tereza and Franchini, Paolo and Kneitz, Susanne and Schartl, Manfred and Meyer, Axel}, title = {Transcriptomics of two evolutionary novelties: how to make a sperm-transfer organ out of an anal fin and a sexually selected "sword" out of a caudal fin}, series = {Ecology and Evolution}, volume = {5}, journal = {Ecology and Evolution}, number = {4}, doi = {10.1002/ece3.1390}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-144139}, pages = {848-864}, year = {2015}, abstract = {Swords are exaggerated male ornaments of swordtail fishes that have been of great interest to evolutionary biologists ever since Darwin described them in the Descent of Man (1871). They are a novel sexually selected trait derived from modified ventral caudal fin rays and are only found in the genus Xiphophorus. Another phylogenetically more widespread and older male trait is the gonopodium, an intromittent organ found in all poeciliid fishes, that is derived from a modified anal fin. Despite many evolutionary and behavioral studies on both traits, little is known so far about the molecular mechanisms underlying their development. By investigating transcriptomic changes (utilizing a RNA-Seq approach) in response to testosterone treatment in the swordtail fish, Xiphophorus hellerii, we aimed to better understand the architecture of the gene regulatory networks underpinning the development of these two evolutionary novelties. Large numbers of genes with tissue-specific expression patterns were identified. Among the sword genes those involved in embryonic organ development, sexual character development and coloration were highly expressed, while in the gonopodium rather more morphogenesis-related genes were found. Interestingly, many genes and genetic pathways are shared between both developing novel traits derived from median fins: the sword and the gonopodium. Our analyses show that a larger set of gene networks was co-opted during the development and evolution of the older gonopodium than in the younger, and morphologically less complex trait, the sword. We provide a catalog of candidate genes for future efforts to dissect the development of those sexually selected exaggerated male traits in swordtails.}, language = {en} } @article{SimonRauskolbGunnersenetal.2015, author = {Simon, Christian M. and Rauskolb, Stefanie and Gunnersen, Jennifer M. and Holtmann, Bettina and Drepper, Carsten and Dombert, Benjamin and Braga, Massimiliano and Wiese, Stefan and Jablonka, Sibylle and P{\"u}hringer, Dirk and Zielasek, J{\"u}rgen and Hoeflich, Andreas and Silani, Vincenzo and Wolf, Eckhard and Kneitz, Susanne and Sommer, Claudia and Toyka, Klaus V. and Sendtner, Michael}, title = {Dysregulated IGFBP5 expression causes axon degeneration and motoneuron loss in diabetic neuropathy}, series = {Acta Neuropathologica}, volume = {130}, journal = {Acta Neuropathologica}, doi = {10.1007/s00401-015-1446-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-154569}, pages = {373 -- 387}, year = {2015}, abstract = {Diabetic neuropathy (DNP), afflicting sensory and motor nerve fibers, is a major complication in diabetes.The underlying cellular mechanisms of axon degeneration are poorly understood. IGFBP5, an inhibitory binding protein for insulin-like growth factor 1 (IGF1) is highly up-regulated in nerve biopsies of patients with DNP. We investigated the pathogenic relevance of this finding in transgenic mice overexpressing IGFBP5 in motor axons and sensory nerve fibers. These mice develop motor axonopathy and sensory deficits similar to those seen in DNP. Motor axon degeneration was also observed in mice in which the IGF1 receptor(IGF1R) was conditionally depleted in motoneurons, indicating that reduced activity of IGF1 on IGF1R in motoneurons is responsible for the observed effect. These data provide evidence that elevated expression of IGFBP5 in diabetic nerves reduces the availability of IGF1 for IGF1R on motor axons, thus leading to progressive neurodegeneration. Inhibition of IGFBP5 could thus offer novel treatment strategies for DNP.}, language = {en} } @article{KarulinKaracsonyZhangetal.2015, author = {Karulin, Alexey Y. and Karacsony, Kinga and Zhang, Wenji and Targoni, Oleg S. and Moldova, Ioana and Dittrich, Marcus and Sundararaman, Srividya and Lehmann, Paul V.}, title = {ELISPOTs produced by CD8 and CD4 cells follow Log Normal size distribution permitting objective counting}, series = {Cells}, volume = {4}, journal = {Cells}, number = {1}, doi = {10.3390/cells4010056}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-149648}, pages = {56-70}, year = {2015}, abstract = {Each positive well in ELISPOT assays contains spots of variable sizes that can range from tens of micrometers up to a millimeter in diameter. Therefore, when it comes to counting these spots the decision on setting the lower and the upper spot size thresholds to discriminate between non-specific background noise, spots produced by individual T cells, and spots formed by T cell clusters is critical. If the spot sizes follow a known statistical distribution, precise predictions on minimal and maximal spot sizes, belonging to a given T cell population, can be made. We studied the size distributional properties of IFN-γ, IL-2, IL-4, IL-5 and IL-17 spots elicited in ELISPOT assays with PBMC from 172 healthy donors, upon stimulation with 32 individual viral peptides representing defined HLA Class I-restricted epitopes for CD8 cells, and with protein antigens of CMV and EBV activating CD4 cells. A total of 334 CD8 and 80 CD4 positive T cell responses were analyzed. In 99.7\% of the test cases, spot size distributions followed Log Normal function. These data formally demonstrate that it is possible to establish objective, statistically validated parameters for counting T cell ELISPOTs.}, language = {en} } @article{GarciaMartinezBrunkAvalosetal.2015, author = {Garc{\´i}a-Mart{\´i}nez, Jorge and Brunk, Michael and Avalos, Javier and Terpitz, Ulrich}, title = {The CarO rhodopsin of the fungus Fusarium fujikuroi is a light-driven proton pump that retards spore germination}, series = {Scientific Reports}, volume = {5}, journal = {Scientific Reports}, number = {7798}, doi = {10.1038/srep07798}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-149049}, year = {2015}, abstract = {Rhodopsins are membrane-embedded photoreceptors found in all major taxonomic kingdoms using retinal as their chromophore. They play well-known functions in different biological systems, but their roles in fungi remain unknown. The filamentous fungus Fusarium fujikuroi contains two putative rhodopsins, CarO and OpsA. The gene carO is light-regulated, and the predicted polypeptide contains all conserved residues required for proton pumping. We aimed to elucidate the expression and cellular location of the fungal rhodopsin CarO, its presumed proton-pumping activity and the possible effect of such function on F. fujikuroi growth. In electrophysiology experiments we confirmed that CarO is a green-light driven proton pump. Visualization of fluorescent CarO-YFP expressed in F. fujikuroi under control of its native promoter revealed higher accumulation in spores (conidia) produced by light-exposed mycelia. Germination analyses of conidia from carO\(^{-}\) mutant and carO\(^{+}\) control strains showed a faster development of light-exposed carO-germlings. In conclusion, CarO is an active proton pump, abundant in light-formed conidia, whose activity slows down early hyphal development under light. Interestingly, CarO-related rhodopsins are typically found in plant-associated fungi, where green light dominates the phyllosphere. Our data provide the first reliable clue on a possible biological role of a fungal rhodopsin.}, language = {en} } @article{LeikamHufnagelOttoetal.2015, author = {Leikam, C and Hufnagel, AL and Otto, C and Murphy, DJ and M{\"u}hling, B and Kneitz, S and Nanda, I and Schmid, M and Wagner, TU and Haferkamp, S and Br{\"o}cker, E-B and Schartl, M and Meierjohann, S}, title = {In vitro evidence for senescent multinucleated melanocytes as a source for tumor-initiating cells}, series = {Cell Death and Disease}, volume = {6}, journal = {Cell Death and Disease}, number = {e1711}, doi = {10.1038/cddis.2015.71}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-148718}, year = {2015}, abstract = {Oncogenic signaling in melanocytes results in oncogene-induced senescence (OIS), a stable cell-cycle arrest frequently characterized by a bi-or multinuclear phenotype that is considered as a barrier to cancer progression. However, the long-sustained conviction that senescence is a truly irreversible process has recently been challenged. Still, it is not known whether cells driven into OIS can progress to cancer and thereby pose a potential threat. Here, we show that prolonged expression of the melanoma oncogene N-RAS\(^{61K}\) in pigment cells overcomes OIS by triggering the emergence of tumor-initiating mononucleated stem-like cells from senescent cells. This progeny is dedifferentiated, highly proliferative, anoikis-resistant and induces fast growing, metastatic tumors. Our data describe that differentiated cells, which are driven into senescence by an oncogene, use this senescence state as trigger for tumor transformation, giving rise to highly aggressive tumor-initiating cells. These observations provide the first experimental in vitro evidence for the evasion of OIS on the cellular level and ensuing transformation.}, language = {en} } @article{EhmannSauerKittel2015, author = {Ehmann, Nadine and Sauer, Markus and Kittel, Robert J.}, title = {Super-resolution microscopy of the synaptic active zone}, series = {Frontiers in Cellular Neuroscience}, volume = {9}, journal = {Frontiers in Cellular Neuroscience}, number = {7}, doi = {10.3389/fncel.2015.00007}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-148997}, year = {2015}, abstract = {Brain function relies on accurate information transfer at chemical synapses. At the presynaptic active zone (AZ) a variety of specialized proteins are assembled to complex architectures, which set the basis for speed, precision and plasticity of synaptic transmission. Calcium channels are pivotal for the initiation of excitation-secretion coupling and, correspondingly, capture a central position at the AZ. Combining quantitative functional studies with modeling approaches has provided predictions of channel properties, numbers and even positions on the nanometer scale. However, elucidating the nanoscopic organization of the surrounding protein network requires direct ultrastructural access. Without this information, knowledge of molecular synaptic structure-function relationships remains incomplete. Recently, super-resolution microscopy (SRM) techniques have begun to enter the neurosciences. These approaches combine high spatial resolution with the molecular specificity of fluorescence microscopy. Here, we discuss how SRM can be used to obtain information on the organization of AZ proteins}, language = {en} } @article{HerwegHansmeierOttoetal.2015, author = {Herweg, Jo-Ana and Hansmeier, Nicole and Otto, Andreas and Geffken, Anna C. and Subbarayal, Prema and Prusty, Bhupesh K. and Becher, D{\"o}rte and Hensel, Michael and Schaible, Ulrich E. and Rudel, Thomas and Hilbi, Hubert}, title = {Purification and proteomics of pathogen-modified vacuoles and membranes}, series = {Frontiers in Cellular and Infection Microbiology}, volume = {5}, journal = {Frontiers in Cellular and Infection Microbiology}, number = {48}, doi = {10.3389/fcimb.2015.00048}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-151823}, year = {2015}, abstract = {Certain pathogenic bacteria adopt an intracellular lifestyle and proliferate in eukaryotic host cells. The intracellular niche protects the bacteria from cellular and humoral components of the mammalian immune system, and at the same time, allows the bacteria to gain access to otherwise restricted nutrient sources. Yet, intracellular protection and access to nutrients comes with a price, i.e., the bacteria need to overcome cell-autonomous defense mechanisms, such as the bactericidal endocytic pathway. While a few bacteria rupture the early phagosome and escape into the host cytoplasm, most intracellular pathogens form a distinct, degradation-resistant and replication-permissive membranous compartment. Intracellular bacteria that form unique pathogen vacuoles include Legionella, Mycobacterium, Chlamydia, Simkania, and Salmonella species. In order to understand the formation of these pathogen niches on a global scale and in a comprehensive and quantitative manner, an inventory of compartment-associated host factors is required. To this end, the intact pathogen compartments need to be isolated, purified and biochemically characterized. Here, we review recent progress on the isolation and purification of pathogen-modified vacuoles and membranes, as well as their proteomic characterization by mass spectrometry and different validation approaches. These studies provide the basis for further investigations on the specific mechanisms of pathogen-driven compartment formation.}, language = {en} } @article{Morriswood2015, author = {Morriswood, Brooke}, title = {Form, fabric, and function of a flagellum-associated cytoskeletal structure.}, series = {Cells}, volume = {4}, journal = {Cells}, number = {4}, doi = {10.3390/cells4040726}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-149467}, pages = {726-747}, year = {2015}, abstract = {Trypanosoma brucei is a uniflagellated protist and the causative agent of African trypanosomiasis, a neglected tropical disease. The single flagellum of T. brucei is essential to a number of cellular processes such as motility, and has been a longstanding focus of scientific enquiry. A number of cytoskeletal structures are associated with the flagellum in T. brucei, and one such structure—a multiprotein complex containing the repeat motif protein TbMORN1—is the focus of this review. The TbMORN1-containing complex, which was discovered less than ten years ago, is essential for the viability of the mammalian-infective form of T. brucei. The complex has an unusual asymmetric morphology, and is coiled around the flagellum to form a hook shape. Proteomic analysis using the proximity-dependent biotin identification (BioID) technique has elucidated a number of its components. Recent work has uncovered a role for TbMORN1 in facilitating protein entry into the cell, thus providing a link between the cytoskeleton and the endomembrane system. This review summarises the extant data on the complex, highlights the outstanding questions for future enquiry, and provides speculation as to its possible role in a size-exclusion mechanism for regulating protein entry. The review additionally clarifies the nomenclature associated with this topic, and proposes the adoption of the term "hook complex" to replace the former name "bilobe" to describe the complex.}, language = {en} } @article{DuehringGermerodtSkerkaetal.2015, author = {D{\"u}hring, Sybille and Germerodt, Sebastian and Skerka, Christine and Zipfel, Peter F. and Dandekar, Thomas and Schuster, Stefan}, title = {Host-pathogen interactions between the human innate immune system and Candida albicans - understanding and modeling defense and evasion strategies}, series = {Frontiers in Microbiology}, volume = {6}, journal = {Frontiers in Microbiology}, number = {625}, doi = {10.3389/fmicb.2015.00625}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-151621}, year = {2015}, abstract = {The diploid, polymorphic yeast Candida albicans is one of the most important human pathogenic fungi. C. albicans can grow, proliferate and coexist as a commensal on or within the human host for a long time. However, alterations in the host environment can render C. albicans virulent. In this review, we describe the immunological cross-talk between C. albicans and the human innate immune system. We give an overview in form of pairs of human defense strategies including immunological mechanisms as well as general stressors such as nutrient limitation, pH, fever etc. and the corresponding fungal response and evasion mechanisms. Furthermore, Computational Systems Biology approaches to model and investigate these complex interactions are highlighted with a special focus on game-theoretical methods and agent-based models. An outlook on interesting questions to be tackled by Systems Biology regarding entangled defense and evasion mechanisms is given.}, language = {en} }