TY - JOUR A1 - Schubert, Frank K. A1 - Hagedorn, Nicolas A1 - Yoshii, Taishi A1 - Helfrich-Förster, Charlotte A1 - Rieger, Dirk T1 - Neuroanatomical details of the lateral neurons of Drosophila melanogaster support their functional role in the circadian system JF - Journal of Comparative Neurology N2 - Drosophila melanogaster is a long-standing model organism in the circadian clock research. A major advantage is the relative small number of about 150 neurons, which built the circadian clock in Drosophila. In our recent work, we focused on the neuroanatomical properties of the lateral neurons of the clock network. By applying the multicolor-labeling technique Flybow we were able to identify the anatomical similarity of the previously described E2 subunit of the evening oscillator of the clock, which is built by the 5th small ventrolateral neuron (5th s-LNv) and one ITP positive dorsolateral neuron (LNd). These two clock neurons share the same spatial and functional properties. We found both neurons innervating the same brain areas with similar pre- and postsynaptic sites in the brain. Here the anatomical findings support their shared function as a main evening oscillator in the clock network like also found in previous studies. A second quite surprising finding addresses the large lateral ventral PDF-neurons (l-LNvs). We could show that the four hardly distinguishable l-LNvs consist of two subgroups with different innervation patterns. While three of the neurons reflect the well-known branching pattern reproduced by PDF immunohistochemistry, one neuron per brain hemisphere has a distinguished innervation profile and is restricted only to the proximal part of the medulla-surface. We named this neuron “extra” l-LNv (l-LNvx). We suggest the anatomical findings reflect different functional properties of the two l-LNv subgroups. KW - circadian clock neurons KW - Drosophila melanogaster KW - flybow KW - morphology KW - RRID: AB_760350 KW - RRID: AB_2315460 KW - RRID: AB_2314242 KW - RRID: AB_2315311 KW - RRID: AB_2314041 KW - RRID: AB_300798 Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-234477 VL - 526 ER - TY - JOUR A1 - Flunkert, Julia A1 - Maierhofer, Anna A1 - Dittrich, Marcus A1 - Müller, Tobias A1 - Horvath, Steve A1 - Nanda, Indrajit A1 - Haaf, Thomas T1 - Genetic and epigenetic changes in clonal descendants of irradiated human fibroblasts JF - Experimental Cell Research N2 - To study delayed genetic and epigenetic radiation effects, which may trigger radiation-induced carcinogenesis, we have established single-cell clones from irradiated and non-irradiated primary human fibroblasts. Stable clones were endowed with the same karyotype in all analyzed metaphases after 20 population doublings (PDs), whereas unstable clones displayed mosaics of normal and abnormal karyotypes. To account for variation in radiation sensitivity, all experiments were performed with two different fibroblast strains. After a single X-ray dose of 2 Gy more than half of the irradiated clones exhibited radiation-induced genome instability (RIGI). Irradiated clones displayed an increased rate of loss of chromosome Y (LOY) and copy number variations (CNVs), compared to controls. CNV breakpoints clustered in specific chromosome regions, in particular 3p14.2 and 7q11.21, coinciding with common fragile sites. CNVs affecting the FHIT gene in FRA3B were observed in independent unstable clones and may drive RIGI. Bisulfite pyrosequencing of control clones and the respective primary culture revealed global hypomethylation of ALU, LINE-1, and alpha-satellite repeats as well as rDNA hypermethylation during in vitro ageing. Irradiated clones showed further reduced ALU and alpha-satellite methylation and increased rDNA methylation, compared to controls. Methylation arrays identified several hundred differentially methylated genes and several enriched pathways associated with in vitro ageing. Methylation changes in 259 genes and the MAP kinase signaling pathway were associated with delayed radiation effects (after 20 PDs). Collectively, our results suggest that both genetic (LOY and CNVs) and epigenetic changes occur in the progeny of exposed cells that were not damaged directly by irradiation, likely contributing to radiation-induced carcinogenesis. We did not observe epigenetic differences between stable and unstable irradiated clones. The fact that the DNA methylation (DNAm) age of clones derived from the same primary culture varied greatly suggests that DNAm age of a single cell (represented by a clone) can be quite different from the DNAm age of a tissue. We propose that DNAm age reflects the emergent property of a large number of individual cells whose respective DNAm ages can be highly variable. KW - copy number variation (CNV) KW - delayed radiation effects KW - DNA methylation (DNAm) age KW - global DNA methylation KW - loss of chromosome Y (LOY); KW - methylation array analysis KW - radiation-induced genome instability (RIGI) Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-228177 VL - 370 ER - TY - JOUR A1 - Baluapuri, Apoorva A1 - Hofstetter, Julia A1 - Dudvarski Stankovic, Nevenka A1 - Endres, Theresa A1 - Bhandare, Pranjali A1 - Vos, Seychelle Monique A1 - Adhikari, Bikash A1 - Schwarz, Jessica Denise A1 - Narain, Ashwin A1 - Vogt, Markus A1 - Wang, Shuang-Yan A1 - Düster, Robert A1 - Jung, Lisa Anna A1 - Vanselow, Jens Thorsten A1 - Wiegering, Armin A1 - Geyer, Matthias A1 - Maric, Hans Michael A1 - Gallant, Peter A1 - Walz, Susanne A1 - Schlosser, Andreas A1 - Cramer, Patrick A1 - Eilers, Martin A1 - Wolf, Elmar T1 - MYC Recruits SPT5 to RNA Polymerase II to Promote Processive Transcription Elongation JF - Molecular Cell N2 - The MYC oncoprotein binds to promoter-proximal regions of virtually all transcribed genes and enhances RNA polymerase II (Pol II) function, but its precise mode of action is poorly understood. Using mass spectrometry of both MYC and Pol II complexes, we show here that MYC controls the assembly of Pol II with a small set of transcription elongation factors that includes SPT5, a subunit of the elongation factor DSIF. MYC directly binds SPT5, recruits SPT5 to promoters, and enables the CDK7-dependent transfer of SPT5 onto Pol II. Consistent with known functions of SPT5, MYC is required for fast and processive transcription elongation. Intriguingly, the high levels of MYC that are expressed in tumors sequester SPT5 into non-functional complexes, thereby decreasing the expression of growth-suppressive genes. Altogether, these results argue that MYC controls the productive assembly of processive Pol II elongation complexes and provide insight into how oncogenic levels of MYC permit uncontrolled cellular growth. KW - MYC KW - SPT5 KW - SUPT5H KW - SPT6 KW - RNA polymerase II KW - transcription KW - elongation rate KW - processivity KW - directionality KW - tumorigenesis Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-221438 VL - 74 ER - TY - JOUR A1 - Göttlich, Claudia A1 - Kunz, Meik A1 - Zapp, Cornelia A1 - Nietzer, Sarah L. A1 - Walles, Heike A1 - Dandekar, Thomas A1 - Dandekar, Gudrun T1 - A combined tissue-engineered/in silico signature tool patient stratification in lung cancer JF - Molecular Oncology N2 - Patient-tailored therapy based on tumor drivers is promising for lung cancer treatment. For this, we combined in vitro tissue models with in silico analyses. Using individual cell lines with specific mutations, we demonstrate a generic and rapid stratification pipeline for targeted tumor therapy. We improve in vitro models of tissue conditions by a biological matrix-based three-dimensional (3D) tissue culture that allows in vitro drug testing: It correctly shows a strong drug response upon gefitinib (Gef) treatment in a cell line harboring an EGFR-activating mutation (HCC827), but no clear drug response upon treatment with the HSP90 inhibitor 17AAG in two cell lines with KRAS mutations (H441, A549). In contrast, 2D testing implies wrongly KRAS as a biomarker for HSP90 inhibitor treatment, although this fails in clinical studies. Signaling analysis by phospho-arrays showed similar effects of EGFR inhibition by Gef in HCC827 cells, under both 2D and 3D conditions. Western blot analysis confirmed that for 3D conditions, HSP90 inhibitor treatment implies different p53 regulation and decreased MET inhibition in HCC827 and H441 cells. Using in vitro data (western, phospho-kinase array, proliferation, and apoptosis), we generated cell line-specific in silico topologies and condition-specific (2D, 3D) simulations of signaling correctly mirroring in vitro treatment responses. Networks predict drug targets considering key interactions and individual cell line mutations using the Human Protein Reference Database and the COSMIC database. A signature of potential biomarkers and matching drugs improve stratification and treatment in KRAS-mutated tumors. In silico screening and dynamic simulation of drug actions resulted in individual therapeutic suggestions, that is, targeting HIF1A in H441 and LKB1 in A549 cells. In conclusion, our in vitro tumor tissue model combined with an in silico tool improves drug effect prediction and patient stratification. Our tool is used in our comprehensive cancer center and is made now publicly available for targeted therapy decisions. KW - 3D lung tumor model KW - Boolean signaling network KW - chemoresistance KW - HSP90 inhibitor KW - insilico drug screening too KW - KRAS mutation signature Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-233137 VL - 12 ER - TY - JOUR A1 - Seitz, Nicola A1 - vanEngelsdorp, Dennis A1 - Leonhardt, Sara D. T1 - Conserving bees in destroyed landscapes: The potentials of reclaimed sand mines JF - Global Ecology and Conservation N2 - Sand mines represent anthropogenically impacted habitats found worldwide, which bear potential for bee conservation. Although floral resources can be limited at these habitats, vegetation free patches of open sandy soils and embankments may offer good nesting possibilities for sand restricted and other bees. We compared bee communities as found in three reclaimed sand mines and at adjacent roadside meadows in Maryland, USA, over two years. Both sand mines and roadsides hosted diverse bee communities with 111 and 88 bee species, respectively. Bee abundances as well as richness and Shannon diversity of bee species were higher in sand mines than at roadsides and negatively correlated with the percentage of vegetational ground cover. Species composition also differed significantly between habitats. Sand mines hosted a higher proportion of ground nesters, more uncommon and more ‘sand loving’ bees similar to natural sandy areas of Maryland. Despite the destruction of the original pre-mining habitat, sand mines thus appear to represent a unique habitat for wild bees, particularly when natural vegetation and open sand spots are encouraged. Considering habitat loss, the lack of natural disturbance regimes, and ongoing declines of wild bees, sand mines could add promising opportunities for bee conservation which has hitherto mainly focused on agricultural and urban habitats. KW - bee conservation KW - bee decline KW - habitat restoration KW - land use KW - wild bees KW - ground nesters Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-235877 VL - 19 ER - TY - JOUR A1 - van de Peppel, L. J. J. A1 - Aanen, D. K. A1 - Biedermann, P. H. W. T1 - Low intraspecific genetic diversity indicates asexuality and vertical transmission in the fungal cultivars of ambrosia beetles JF - Fungal Ecology N2 - Ambrosia beetles farm ascomycetous fungi in tunnels within wood. These ambrosia fungi are regarded asexual, although population genetic proof is missing. Here we explored the intraspecific genetic diversity of Ambrosiella grosmanniae and Ambrosiella hartigii (Ascomycota: Microascales), the mutualists of the beetles Xylosandrus germanus and Anisandrus dispar. By sequencing five markers (ITS, LSU, TEF1α, RPB2, β-tubulin) from several fungal strains, we show that X. germanus cultivates the same two clones of A. grosmanniae in the USA and in Europe, whereas A. dispar is associated with a single A. hartigii clone across Europe. This low genetic diversity is consistent with predominantly asexual vertical transmission of Ambrosiella cultivars between beetle generations. This clonal agriculture is a remarkable case of convergence with fungus-farming ants, given that both groups have a completely different ecology and evolutionary history. KW - clonal fungiculture KW - ambrosia fungus KW - Ambrosiella KW - vertical transmission KW - symbiosis KW - Xylosandrus KW - Anisandrus KW - asexuality KW - genetic diversity Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-232161 VL - 32 ER - TY - JOUR A1 - Grebinyk, Anna A1 - Grebinyk, Sergii A1 - Prylutska, Svitlana A1 - Ritter, Uwe A1 - Matyshevska, Olga A1 - Dandekar, Thomas A1 - Frohme, Marcus T1 - C60 fullerene accumulation in human leukemic cells and perspectives of LED-mediated photodynamic therapy JF - Free Radical Biology and Medicine N2 - Recent progress in nanobiotechnology has attracted interest to a biomedical application of the carbon nanostructure C60 fullerene since it possesses a unique structure and versatile biological activity. C60 fullerene potential application in the frame of cancer photodynamic therapy (PDT) relies on rapid development of new light sources as well as on better understanding of the fullerene interaction with cells. The aim of this study was to analyze C60 fullerene effects on human leukemic cells (CCRF-CEM) in combination with high power single chip light-emitting diodes (LEDs) light irradiation of different wavelengths: ultraviolet (UV, 365 nm), violet (405 nm), green (515 nm) and red (632 nm). The time-dependent accumulation of fullerene C60 in CCRF-CEM cells up to 250 ng/106 cells at 24 h with predominant localization within mitochondria was demonstrated with immunocytochemical staining and liquid chromatography mass spectrometry. In a cell viability assay we studied photoexcitation of the accumulated C60 nanostructures with ultraviolet or violet LEDs and could prove that significant phototoxic effects did arise. A less pronounced C60 fullerene phototoxic effect was observed after irradiation with green, and no effect was detected with red light. A C60 fullerene photoactivation with violet light induced substantial ROS generation and apoptotic cell death, confirmed by caspase3/7 activation and plasma membrane phosphatidylserine externalization. Our work proved C60 fullerene ability to induce apoptosis of leukemic cells after photoexcitation with high power single chip 405 nm LED as a light source. This underlined the potential for application of C60 nanostructure as a photosensitizer for anticancer therapy. KW - C-60 fullerene KW - photodanamic therapy KW - LEDs KW - leukemic cells KW - immunocytochemistry KW - HPLC-ESI-MS KW - apoptosis Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-228245 VL - 124 ER - TY - JOUR A1 - Hofrichter, Michaela A. H. A1 - Doll, Julia A1 - Habibi, Haleh A1 - Enayati, Samaneh A1 - Mehrjardi, Mohammad Yahya Vahidi A1 - Müller, Tobias A1 - Dittrich, Marcus A1 - Haaf, Thomas A1 - Vona, Barbara T1 - Exome-wide copy number variation analysis identifies a COL9A1 in frame deletion that is associated with hearing loss JF - European Journal of Medical Genetics N2 - Pathogenic variants in COL9A1 are primarily associated with autosomal recessive Stickler syndrome. Patients with COL9A1-associated Stickler syndrome (STL) present hearing loss (HL), ophthalmic manifestations and skeletal abnormalities. However, the clinical spectrum of patients with COL9A1 variants can also include multiple epiphyseal dysplasia, as well as non-syndromic HL that was observed in one previously reported proband. Exome sequencing was performed on the genomic DNA of an Iranian patient and his affected brother who both report non-syndromic HL. A 44.6 kb homozygous in-frame deletion spanning exons 6 to 33 of COL9A1 was detected via exome-based copy number variation analysis. The deleted exons were confirmed by PCR in the patient and his affected brother, who both have non-syndromic HL. Segregation analysis via qPCR confirmed the parents as heterozygous deletion carriers. Breakpoint analysis mapped the homozygous deletion spanning introns 5 to 33 (g.70,948,188_70,997,277del, NM_001851.4(COL9A1):c.697–3754_2112+769del, p.(Phe233_Ser704del), with an additional 67 bp of inserted intronic sequence that may have originated due to a fork stalling and template switching/microhomology-mediated break-induced replication (FoSTeS/MMBIR) mechanism. This mechanism has not been previously implicated in HL or STL. This is also the first reported copy number variation in COL9A1 that was identified through an exome data set in an Iranian family with apparent non-syndromic HL. The present study emphasizes the importance of exome-wide copy number variation analysis in molecular diagnosis and provides supporting evidence to associate COL9A1 with autosomal recessive non-syndromic HL. KW - COL9A1 KW - copy number variation KW - FoSTeS/MMBIR mechanism KW - non-syndromic hearing loss KW - Stickler syndrome Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-322008 VL - 62 ER - TY - JOUR A1 - Chen, Wei-Hua A1 - Lu, Guanting A1 - Chen, Xiao A1 - Zhao, Xing-Ming A1 - Bork, Peer T1 - OGEE v2: an update of the online gene essentiality database with special focus on differentially essential genes in human cancer cell lines JF - Nucleic Acids Research N2 - OGEE is an Online GEne Essentiality database. To enhance our understanding of the essentiality of genes, in OGEE we collected experimentally tested essential and non-essential genes, as well as associated gene properties known to contribute to gene essentiality. We focus on large-scale experiments, and complement our data with text-mining results. We organized tested genes into data sets according to their sources, and tagged those with variable essentiality statuses across data sets as conditionally essential genes, intending to highlight the complex interplay between gene functions and environments/experimental perturbations. Developments since the last public release include increased number of species and gene essentiality data sets, inclusion of non-coding essential sequences and genes with intermediate essentiality statuses. In addition, we included 16 essentiality data sets from cancer cell lines, corresponding to 9 human cancers; with OGEE, users can easily explore the shared and differentially essential genes within and between cancer types. These genes, especially those derived from cell lines that are similar to tumor samples, could reveal the oncogenic drivers, paralogous gene expression pattern and chromosomal structure of the corresponding cancer types, and can be further screened to identify targets for cancer therapy and/or new drug development. OGEE is freely available at http://ogee.medgenius.info. KW - human cancer cell lines KW - gene essentiality database KW - OGEE v2 Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-181334 VL - 45 IS - D1 ER - TY - JOUR A1 - Link, Jana A1 - Paouneskou, Dimitra A1 - Velkova, Maria A1 - Daryabeigi, Anahita A1 - Laos, Triin A1 - Labella, Sara A1 - Barroso, Consuelo A1 - Pacheco Piñol, Sarai A1 - Montoya, Alex A1 - Kramer, Holger A1 - Woglar, Alexander A1 - Baudrimont, Antoine A1 - Markert, Sebastian Mathias A1 - Stigloher, Christian A1 - Martinez-Perez, Enrique A1 - Dammermann, Alexander A1 - Alsheimer, Manfred A1 - Zetka, Monique A1 - Jantsch, Verena T1 - Transient and Partial Nuclear Lamina Disruption Promotes Chromosome Movement in Early Meiotic Prophase JF - Developmental Cell N2 - Meiotic chromosome movement is important for the pairwise alignment of homologous chromosomes, which is required for correct chromosome segregation. Movement is driven by cytoplasmic forces, transmitted to chromosome ends by nuclear membrane-spanning proteins. In animal cells, lamins form a prominent scaffold at the nuclear periphery, yet the role lamins play in meiotic chromosome movement is unclear. We show that chromosome movement correlates with reduced lamin association with the nuclear rim, which requires lamin phosphorylation at sites analogous to those that open lamina network crosslinks in mitosis. Failure to remodel the lamina results in delayed meiotic entry, altered chromatin organization, unpaired or interlocked chromosomes, and slowed chromosome movement. The remodeling kinases are delivered to lamins via chromosome ends coupled to the nuclear envelope, potentially enabling crosstalk between the lamina and chromosomal events. Thus, opening the lamina network plays a role in modulating contacts between chromosomes and the nuclear periphery during meiosis. KW - meiosis KW - C. elegans KW - chromosome movement KW - chromosome pairing KW - nuclear envelope KW - lamin Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236901 VL - 45 ER -