TY  - JOUR
A1  - Galluzzi, L.
A1  - Bravo-San Pedro, J. M.
A1  - Vitale, I.
A1  - Aaronson, S. A.
A1  - Abrams, J. M.
A1  - Adam, D.
A1  - Alnemri, E. S.
A1  - Altucci, L.
A1  - Andrews, D.
A1  - Annicchiarico-Petruzelli, M.
A1  - Baehrecke, E. H.
A1  - Bazan, N. G.
A1  - Bertrand, M. J.
A1  - Bianchi, K.
A1  - Blagosklonny, M. V.
A1  - Blomgren, K.
A1  - Borner, C.
A1  - Bredesen, D. E.
A1  - Brenner, C.
A1  - Campanella, M.
A1  - Candi, E.
A1  - Cecconi, F.
A1  - Chan, F. K.
A1  - Chandel, N. S.
A1  - Cheng, E. H.
A1  - Chipuk, J. E.
A1  - Cidlowski, J. A.
A1  - Ciechanover, A.
A1  - Dawson, T. M.
A1  - Dawson, V. L.
A1  - De Laurenzi, V.
A1  - De Maria, R.
A1  - Debatin, K. M.
A1  - Di Daniele, N.
A1  - Dixit, V. M.
A1  - Dynlacht, B. D.
A1  - El-Deiry, W. S.
A1  - Fimia, G. M.
A1  - Flavell, R. A.
A1  - Fulda, S.
A1  - Garrido, C.
A1  - Gougeon, M. L.
A1  - Green, D. R.
A1  - Gronemeyer, H.
A1  - Hajnoczky, G.
A1  - Hardwick, J. M.
A1  - Hengartner, M. O.
A1  - Ichijo, H.
A1  - Joseph, B.
A1  - Jost, P. J.
A1  - Kaufmann, T.
A1  - Kepp, O.
A1  - Klionsky, D. J.
A1  - Knight, R. A.
A1  - Kumar, S.
A1  - Lemasters, J. J.
A1  - Levine, B.
A1  - Linkermann, A.
A1  - Lipton, S. A.
A1  - Lockshin, R. A.
A1  - López-Otín, C.
A1  - Lugli, E.
A1  - Madeo, F.
A1  - Malorni, W.
A1  - Marine, J. C.
A1  - Martin, S. J.
A1  - Martinou, J. C.
A1  - Medema, J. P.
A1  - Meier, P.
A1  - Melino, S.
A1  - Mizushima, N.
A1  - Moll, U.
A1  - Muñoz-Pinedo, C.
A1  - Nuñez, G.
A1  - Oberst, A.
A1  - Panaretakis, T.
A1  - Penninger, J. M.
A1  - Peter, M. E.
A1  - Piacentini, M.
A1  - Pinton, P.
A1  - Prehn, J. H.
A1  - Puthalakath, H.
A1  - Rabinovich, G. A.
A1  - Ravichandran, K. S.
A1  - Rizzuto, R.
A1  - Rodrigues, C. M.
A1  - Rubinsztein, D. C.
A1  - Rudel, T.
A1  - Shi, Y.
A1  - Simon, H. U.
A1  - Stockwell, B. R.
A1  - Szabadkai, G.
A1  - Tait, S. W.
A1  - Tang, H. L.
A1  - Tavernarakis, N.
A1  - Tsujimoto, Y.
A1  - Vanden Berghe, T.
A1  - Vandenabeele, P.
A1  - Villunger, A.
A1  - Wagner, E. F.
A1  - Walczak, H.
A1  - White, E.
A1  - Wood, W. G.
A1  - Yuan, J.
A1  - Zakeri, Z.
A1  - Zhivotovsky, B.
A1  - Melino, G.
A1  - Kroemer, G.
T1  - Essential versus accessory aspects of cell death: recommendations of the NCCD 2015
JF  - Cell Death and Differentiation
N2  - Cells exposed to extreme physicochemical or mechanical stimuli die in an uncontrollable manner, as a result of their immediate structural breakdown. Such an unavoidable variant of cellular demise is generally referred to as 'accidental cell death' (ACD). In most settings, however, cell death is initiated by a genetically encoded apparatus, correlating with the fact that its course can be altered by pharmacologic or genetic interventions. 'Regulated cell death' (RCD) can occur as part of physiologic programs or can be activated once adaptive responses to perturbations of the extracellular or intracellular microenvironment fail. The biochemical phenomena that accompany RCD may be harnessed to classify it into a few subtypes, which often (but not always) exhibit stereotyped morphologic features. Nonetheless, efficiently inhibiting the processes that are commonly thought to cause RCD, such as the activation of executioner caspases in the course of apoptosis, does not exert true cytoprotective effects in the mammalian system, but simply alters the kinetics of cellular demise as it shifts its morphologic and biochemical correlates. Conversely, bona fide cytoprotection can be achieved by inhibiting the transduction of lethal signals in the early phases of the process, when adaptive responses are still operational. Thus, the mechanisms that truly execute RCD may be less understood, less inhibitable and perhaps more homogeneous than previously thought. Here, the Nomenclature Committee on Cell Death formulates a set of recommendations to help scientists and researchers to discriminate between essential and accessory aspects of cell death.
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-121207
VL  - 22
ER  - 
TY  - THES
A1  - Bruttel, Valentin Stefan
T1  - Soluble HLA-G binds to dendritic cells which likely suppresses anti-tumour immune responses in regional lymph nodes in ovarian carcinoma
T1  - Lösliches HLA-G wird von dendritischen Zellen gebunden, was beim Ovarialkarzinom zur Hemmung von Immunraktionen in regionalen Lymphknoten führen kann
N2  - Zusammenfassung

Einleitung 

HLA-G, ein nicht-klassisches HLA bzw. MHC Klasse Ib Molekül, kann sowohl als membrangebundenes als auch als lösliches Molekül verschiedenste Immunzellpopulationen effektiv inhibieren. Unter physiologischen Bedingungen wird HLA-G vor allem in der Plazenta exprimiert, wo es dazu beiträgt den semiallogenen Embryo vor einer Abstoßung durch das mütterliche Immunsystem zu beschützen. Außerdem wird HLA-G in einer Vielzahl von Tumoren wie zum Beispiel in Ovarialkarzinomen überexprimiert. Ziel dieser Arbeit war es besonders die Rolle von löslichem HLA-G im Ovarialkarzinom und die Expression von HLA-G in verschiedenen Subtypen des Ovarialkarzinoms genauer zu untersuchen. 

Ergebnisse

Anhand eines Tissue Microarrays wurde bestätigt dass HLA-G unter physiologischen Bedingungen nur in sehr wenigen Geweben wie Plazenta oder Testes exprimiert wird. Außerdem wurden erstmals auch im Nebennierenmark hohe Expressionslevel detektiert. Im Gegensatz zur physiologischen Expression wurde HLA-G in serösen, muzinösen, endometrioiden und Klarzellkarzinomen und somit in Tumoren aller untersuchten Subtypen des Ovarialkarzinoms detektiert. Am häufigsten war HLA-G in hochgradigen serösen Karzinomen überexprimiert. Hier konnte gezeigt werden dass auf Genexpressionslevel in Ovarialkarzinomen die Expression des immunsuppressiven HLA-G mit der Expression von klassischen MHC Molekülen wie HLA-A, -B oder -C hochsignifikant korreliert. Außerdem konnte in Aszitesproben von Patientinnen mit Ovarialkarzinomen hohe Konzentrationen von löslichem HLA-G nachgewiesen werden. Auch auf metastasierten Tumorzellen in regionalen Lymphknoten war HLA-G nachweisbar. Überraschenderweise wurde aber besonders viel HLA-G auf Dendritischen Zellen in Lymphknoten detektiert. Da in Monozyten und Dendritischen Zellen von gesunden Spendern durch IL-4 oder IL-10 im Gegensatz zu Literatur keine Expression von HLA-G induzierbar war, untersuchten wir ob Dendritische Zellen lösliches HLA-G binden. Es konnte gezeigt werden, dass besonders Dendritische Zellen die in Gegenwart von IL-4, IL-10 und GM-CSF aus Monozyten generiert wurden (DC-10) effektiv lösliches HLA-G über ILT Rezeptoren binden. In Abhängigkeit von ihrer Beladung mit HLA-G hemmen auch fixierte DC-10 Zellen noch die Proliferation von zytotoxischen CD8+ T Zellen. Zudem wurden regulatorische T Zellen induziert. 

Schlussfolgerungen

Besonders in den am häufigsten diagnostizierten hochgradigen serösen Ovarialkarzinomen ist HLA-G in den meisten Fällen überexprimiert. Durch die Expression immunsuppressiver MHC Klasse Ib Moleküle wie HLA-G können wahrscheinlich auch Tumore wachsen, die noch klassische MHC Moleküle exprimieren und aufgrund ihrer Mutationslast eigentlich vom Immunsystem erkannt und eliminiert werden müssten. Lösliches HLA-G könnte zudem lokal Immunantworten gegen Tumorantigene unterdrücken indem es an Dendritische Zellen in regionalen Lymphknoten bindet. Diese Zellen präsentieren nomalerweise zytotoxischen T Zellen Tumorantigene und spielen daher eine entscheidende Rolle in der Entstehung von protektiven Immunantworten. Mit löslichem HLA-G beladene Dendritische Zellen hemmen jedoch die Proliferation von CD8+ T Zellen und induzieren regulatorische T Zellen. Dadurch könnten Ovarialkarzinome “aus der Ferne” auch in metastasenfreien Lymphknoten die Entstehung von gegen den Tumor gerichteten Immunantworten unterdrücken. Dieser erstmals beschriebene Mechanismus könnte auch in anderen malignen Erkrankungen eine Rolle spielen, da lösliches HLA-G in einer Vielzahl von Tumorindikationen nachgewiesen wurde.
N2  - Abstract

Background

HLA-G is a non-classical MHC class I molecule which exerts strong immunosuppressive effects on various immune cells. Several membrane-bound and soluble isoforms are known. Physiologically, HLA-G is predominantly expressed in the placenta, where it contributes to protecting the semi-allogeneic embryo from rejection by the maternal immune system. However, HLA-G is also often upregulated during tumourigenesis, such as in ovarian cancer. The aim of this thesis is to investigate how soluble HLA-G may contribute to local immunosuppression in ovarian carcinomas, and to characterize HLA-G expression in different ovarian carcinoma subtypes and metastases. 

Results

As reported by others, physiological HLA-G expression is restricted to few tissues, such as placenta and testes. Here, HLA-G was also detected in the medulla of the adrenal gland. In contrast, HLA-G expression was frequently detected in tumours of all assessed subtypes of ovarian carcinomas (serous, mucinous, endometrioid and clear cell). Highest expression levels were detected in high-grade serous carcinomas. In primary tumours, expression of HLA-G correlated with expression of classical MHC class I molecules HLA-A, -B and -C.  Surprisingly, high levels of HLA-G were also detected on dendritic cells in local lymph nodes. As no expression of HLA-G was inducible in monocytes or dendritic cells from healthy donors in response to IL-10 or IL-4, we speculated that tumour-derived soluble HLA-G might be transferred to dendritic cells via the lymphatic system. Accordingly, high levels of tumour-derived soluble HLA-G were detected in ovarian cancer ascites samples. In vitro, dendritic cells expanded in the presence of IL-4, IL-10 and GM-CSF (DC-10) were particularly prone to binding high amounts of soluble HLA-G via ILT receptors. Furthermore, HLA-G loaded DC-10 cells inhibited the proliferation of CD8 effector cells and induced regulatory T cells, even when the DC-10 cells had been fixed with paraformaldehyde.
 
Conclusion

The immunosuppressive molecule HLA-G is overexpressed in high-grade serous ovarian carcinomas, which account for the majority of ovarian cancers. In particular tumours with a high mutational burden and intact expression of classical, immunogenic MHC class Ia molecules may use HLA-G to escape from immunosurveillance. Additionally, tumour-derived soluble HLA-G may inhibit adaptive immune responses by binding to dendritic cells in local lymph nodes. Dendritic cells usually play a decisive role in the initiation of adaptive anti-tumour immune responses by presenting tumour antigens to cytotoxic T cells. In contrast, dendritic cells loaded with soluble HLA-G inhibit the proliferation of effector T cells and promote the induction of regulatory T cells. Thus, soluble HLA-G that is transferred to dendritic cells via lymphatic vessels may enable ovarian carcinomas to remotely suppress anti-tumour immune responses in local lymph nodes. This novel immune-escape mechanism may also exist in other solid tumours that express HLA-G.
KW  - HLA-G
KW  - HLA-G
KW  - Dendritische Zelle
KW  - Eierstocktumor
KW  - ovarian cancer
KW  - ovarian carcinoma
KW  - transfer
KW  - dendritic cells
KW  - immune escape
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-127252
ER  - 
TY  - JOUR
A1  - Strube-Bloss, Martin F.
A1  - Brown, Austin
A1  - Spaethe, Johannes
A1  - Schmitt, Thomas
A1  - Rössler, Wolfgang
T1  - Extracting the Behaviorally Relevant Stimulus: Unique Neural Representation of Farnesol, a Component of the Recruitment Pheromone of Bombus terrestris
JF  - PLoS One
N2  - To trigger innate behavior, sensory neural networks are pre-tuned to extract biologically relevant stimuli. Many male-female or insect-plant interactions depend on this phenomenon. Especially communication among individuals within social groups depends on innate behaviors. One example is the efficient recruitment of nest mates by successful bumblebee foragers. Returning foragers release a recruitment pheromone in the nest while they perform a ‘dance’ behavior to activate unemployed nest mates. A major component of this pheromone is the sesquiterpenoid farnesol. How farnesol is processed and perceived by the olfactory system, has not yet been identified. It is much likely that processing farnesol involves an innate mechanism for the extraction of relevant information to trigger a fast and reliable behavioral response. To test this hypothesis, we used population response analyses of 100 antennal lobe (AL) neurons recorded in alive bumblebee workers under repeated stimulation with four behaviorally different, but chemically related odorants (geraniol, citronellol, citronellal and farnesol). The analysis identified a unique neural representation of the recruitment pheromone component compared to the other odorants that are predominantly emitted by flowers. The farnesol induced population activity in the AL allowed a reliable separation of farnesol from all other chemically related odor stimuli we tested. We conclude that the farnesol induced population activity may reflect a predetermined representation within the AL-neural network allowing efficient and fast extraction of a behaviorally relevant stimulus. Furthermore, the results show that population response analyses of multiple single AL-units may provide a powerful tool to identify distinct representations of behaviorally relevant odors.
KW  - instinct
KW  - plant-insect interactions
KW  - pheromones
KW  - bumblebees
KW  - odorants
KW  - principal component analysis
KW  - neurons
KW  - action potentials
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125875
VL  - 10
IS  - 9
ER  - 
TY  - JOUR
A1  - Lichtenstein, Leonie
A1  - Sommerlandt, Frank M. J.
A1  - Spaethe, Johannes
T1  - Dumb and Lazy? A Comparison of Color Learning and Memory Retrieval in Drones and Workers of the Buff-Tailed Bumblebee, Bombus terrestris, by Means of PER Conditioning
JF  - PLoS One
N2  - More than 100 years ago, Karl von Frisch showed that honeybee workers learn and discriminate colors. Since then, many studies confirmed the color learning capabilities of females from various hymenopteran species. Yet, little is known about visual learning and memory in males despite the fact that in most bee species males must take care of their own needs and must find rewarding flowers to obtain food. Here we used the proboscis extension response (PER) paradigm to study the color learning capacities of workers and drones of the bumblebee, Bombus terrestris. Light stimuli were paired with sucrose reward delivered to the insects’ antennae and inducing a reflexive extension of the proboscis. We evaluated color learning (i.e. conditioned PER to color stimuli) in absolute and differential conditioning protocols and mid-term memory retention was measured two hours after conditioning. Different monochromatic light stimuli in combination with neutral density filters were used to ensure that the bumblebees could only use chromatic and not achromatic (e.g. brightness) information. Furthermore, we tested if bees were able to transfer the learned information from the PER conditioning to a novel discrimination task in a Y-maze. Both workers and drones were capable of learning and discriminating between monochromatic light stimuli and retrieved the learned stimulus after two hours. Drones performed as well as workers during conditioning and in the memory test, but failed in the transfer test in contrast to workers. Our data clearly show that bumblebees can learn to associate a color stimulus with a sugar reward in PER conditioning and that both workers and drones reach similar acquisition and mid-term retention performances. Additionally, we provide evidence that only workers transfer the learned information from a Pavlovian to an operant situation.
KW  - memory
KW  - bumblebees
KW  - behavioral conditioning
KW  - honey bees
KW  - flowers
KW  - sucrose
KW  - bees
KW  - learning
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125832
VL  - 10
IS  - 7
ER  - 
TY  - JOUR
A1  - Salat, Daniela
A1  - Winkler, Anja
A1  - Urlaub, Henning
A1  - Gessler, Manfred
T1  - Hey bHLH Proteins Interact with a FBXO45 Containing SCF Ubiquitin Ligase Complex and Induce Its Translocation into the Nucleus
JF  - PLoS One
N2  - The Hey protein family, comprising Hey1, Hey2 and HeyL in mammals, conveys Notch signals in many cell types. The helix-loop-helix (HLH) domain as well as the Orange domain, mediate homo- and heterodimerization of these transcription factors. Although distinct interaction partners have been identified so far, their physiological relevance for Hey functions is still largely unclear. Using a tandem affinity purification approach and mass spectrometry analysis we identified members of an ubiquitin E3-ligase complex consisting of FBXO45, PAM and SKP1 as novel Hey1 associated proteins. There is a direct interaction between Hey1 and FBXO45, whereas FBXO45 is needed to mediate indirect Hey1 binding to SKP1. Expression of Hey1 induces translocation of FBXO45 and PAM into the nucleus. Hey1 is a short-lived protein that is degraded by the proteasome, but there is no evidence for FBXO45-dependent ubiquitination of Hey1. On the contrary, Hey1 mediated nuclear translocation of FBXO45 and its associated ubiquitin ligase complex may extend its spectrum to additional nuclear targets triggering their ubiquitination. This suggests a novel mechanism of action for Hey bHLH factors.
KW  - ubiquitination
KW  - glycerol
KW  - transcription factors
KW  - DNA-binding proteins
KW  - immunoprecipitation
KW  - protein interactions
KW  - protein domains
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125769
VL  - 10
IS  - 6
ER  - 
TY  - JOUR
A1  - Sickel, Wiebke
A1  - Ankenbrand, Markus J.
A1  - Grimmer, Gudrun
A1  - Holzschuh, Andrea
A1  - Härtel, Stephan
A1  - Lanzen, Jonathan
A1  - Steffan-Dewenter, Ingolf
A1  - Keller, Alexander
T1  - Increased efficiency in identifying mixed pollen samples by meta-barcoding with a dual-indexing approach
JF  - BMC Ecology
N2  - Background
Meta-barcoding of mixed pollen samples constitutes a suitable alternative to conventional pollen identification via light microscopy. Current approaches however have limitations in practicability due to low sample throughput and/or inefficient processing methods, e.g. separate steps for amplification and sample indexing.

Results
We thus developed a new primer-adapter design for high throughput sequencing with the Illumina technology that remedies these issues. It uses a dual-indexing strategy, where sample-specific combinations of forward and reverse identifiers attached to the barcode marker allow high sample throughput with a single sequencing run. It does not require further adapter ligation steps after amplification. We applied this protocol to 384 pollen samples collected by solitary bees and sequenced all samples together on a single Illumina MiSeq v2 flow cell. According to rarefaction curves, 2,000–3,000 high quality reads per sample were sufficient to assess the complete diversity of 95% of the samples. We were able to detect 650 different plant taxa in total, of which 95% were classified at the species level. Together with the laboratory protocol, we also present an update of the reference database used by the classifier software, which increases the total number of covered global plant species included in the database from 37,403 to 72,325 (93% increase).

Conclusions
This study thus offers improvements for the laboratory and bioinformatical workflow to existing approaches regarding data quantity and quality as well as processing effort and cost-effectiveness. Although only tested for pollen samples, it is furthermore applicable to other research questions requiring plant identification in mixed and challenging samples.
KW  - pollination ecology
KW  - next generation sequencing
KW  - ITS2
KW  - illumina MiSeq platform
KW  - high throughput sequencing
KW  - DNA barcoding
KW  - NGS
KW  - osmia
KW  - palynolog
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125730
VL  - 15
IS  - 20
ER  - 
TY  - JOUR
A1  - Meierjohann, Svenja
T1  - Hypoxia independent drivers of melanoma angiogenesis
JF  - Frontiers in Oncology
N2  - Tumor angiogenesis is a process which is traditionally regarded as the tumor’s response to low nutrient supply occurring under hypoxic conditions. However, hypoxia is not a pre-requisite for angiogenesis. The fact that even single tumor cells or small tumor cell aggregates are capable of attracting blood vessels reveals the early metastatic capability of tumor cells. This review sheds light on the hypoxia-independent mechanisms of tumor angiogenesis in melanoma.
KW  - melanoma
KW  - angiogenesis
KW  - hypoxia-independent
KW  - reactive oxygen species
KW  - NF-κB
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125586
VL  - 5
IS  - 120
ER  - 
TY  - JOUR
A1  - Subbarayal, Prema
A1  - Karunakaran, Karthika
A1  - Winkler, Ann-Cathrin
A1  - Rother, Marion
A1  - Gonzalez, Erik
A1  - Meyer, Thomas F.
A1  - Rudel, Thomas
T1  - EphrinA2 Receptor (EphA2) Is an Invasion and Intracellular Signaling Receptor for Chlamydia trachomatis
JF  - PLoS Pathogens
N2  - The obligate intracellular bacterium Chlamydia trachomatis invades into host cells to replicate inside a membrane-bound vacuole called inclusion. Multiple different host proteins are recruited to the inclusion and are functionally modulated to support chlamydial development. Invaded and replicating Chlamydia induces a long-lasting activation of the PI3 kinase signaling pathway that is required for efficient replication. We identified the cell surface tyrosine kinase EphrinA2 receptor (EphA2) as a chlamydial adherence and invasion receptor that induces PI3 kinase (PI3K) activation, promoting chlamydial replication. Interfering with binding of C. trachomatis serovar L2 (Ctr) to EphA2, downregulation of EphA2 expression or inhibition of EphA2 activity significantly reduced Ctr infection. Ctr interacts with and activates EphA2 on the cell surface resulting in Ctr and receptor internalization. During chlamydial replication, EphA2 remains active accumulating around the inclusion and interacts with the p85 regulatory subunit of PI3K to support the activation of the PI3K/Akt signaling pathway that is required for normal chlamydial development. Overexpression of full length EphA2, but not the mutant form lacking the intracellular cytoplasmic domain, enhanced PI3K activation and Ctr infection. Despite the depletion of EphA2 from the cell surface, Ctr infection induces upregulation of EphA2 through the activation of the ERK pathway, which keeps the infected cell in an apoptosis-resistant state. The significance of EphA2 as an entry and intracellular signaling receptor was also observed with the urogenital C. trachomatis-serovar D. Our findings provide the first evidence for a host cell surface receptor that is exploited for invasion as well as for receptor-mediated intracellular signaling to facilitate chlamydial replication. In addition, the engagement of a cell surface receptor at the inclusion membrane is a new mechanism by which Chlamydia subverts the host cell and induces apoptosis resistance.
KW  - membrane proteins
KW  - chlamydia infection
KW  - chlamydia trachomatis
KW  - chlamydia
KW  - HeLa cells
KW  - apoptosis
KW  - host cells
KW  - membrane receptor signaling
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125566
VL  - 11
IS  - 4
ER  - 
TY  - JOUR
A1  - Herter, Eva K.
A1  - Stauch, Maria
A1  - Gallant, Maria
A1  - Wolf, Elmar
A1  - Raabe, Thomas
A1  - Gallant, Peter
T1  - snoRNAs are a novel class of biologically relevant Myc targets
JF  - BMC Biology
N2  - Background
Myc proteins are essential regulators of animal growth during normal development, and their deregulation is one of the main driving factors of human malignancies. They function as transcription factors that (in vertebrates) control many growth- and proliferation-associated genes, and in some contexts contribute to global gene regulation.

Results
We combine chromatin immunoprecipitation-sequencing (ChIPseq) and RNAseq approaches in Drosophila tissue culture cells to identify a core set of less than 500 Myc target genes, whose salient function resides in the control of ribosome biogenesis. Among these genes we find the non-coding snoRNA genes as a large novel class of Myc targets. All assayed snoRNAs are affected by Myc, and many of them are subject to direct transcriptional activation by Myc, both in Drosophila and in vertebrates. The loss of snoRNAs impairs growth during normal development, whereas their overexpression increases tumor mass in a model for neuronal tumors.

Conclusions
This work shows that Myc acts as a master regulator of snoRNP biogenesis. In addition, in combination with recent observations of snoRNA involvement in human cancer, it raises the possibility that Myc’s transforming effects are partially mediated by this class of non-coding transcripts.
KW  - Drosophila
KW  - ribosome
KW  - snoRNA
KW  - Myc Transcription
KW  - growth
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-124956
VL  - 13
IS  - 25
ER  - 
TY  - JOUR
A1  - Adolfi, Mateus C.
A1  - Carreira, Ana C. O.
A1  - Jesus, Lázaro W. O.
A1  - Bogerd, Jan
A1  - Funes, Rejane M.
A1  - Schartl, Manfred
A1  - Sogayar, Mari C.
A1  - Borella, Maria I.
T1  - Molecular cloning and expression analysis of dmrt1 and sox9 during gonad development and male reproductive cycle in the lambari fish, Astyanax altiparanae
JF  - Reproductive Biology and Endocrinology
N2  - Background
The dmrt1 and sox9 genes have a well conserved function related to testis formation in vertebrates, and the group of fish presents a great diversity of species and reproductive mechanisms. The lambari fish (Astyanax altiparanae) is an important Neotropical species, where studies on molecular level of sex determination and gonad maturation are scarce.

Methods
Here, we employed molecular cloning techniques to analyze the cDNA sequences of the dmrt1 and sox9 genes, and describe the expression pattern of those genes during development and the male reproductive cycle by qRT-PCR, and related to histology of the gonad.

Results
Phylogenetic analyses of predicted amino acid sequences of dmrt1 and sox9 clustered A. altiparanae in the Ostariophysi group, which is consistent with the morphological phylogeny of this species. Studies of the gonad development revealed that ovary formation occurred at 58 days after hatching (dah), 2 weeks earlier than testis formation. Expression studies of sox9 and dmrt1 in different tissues of adult males and females and during development revealed specific expression in the testis, indicating that both genes also have a male-specific role in the adult. During the period of gonad sex differentiation, dmrt1 seems to have a more significant role than sox9. During the male reproductive cycle dmrt1 and sox9 are down-regulated after spermiation, indicating a role of these genes in spermatogenesis.

Conclusions
For the first time the dmrt1 and sox9 were cloned in a Characiformes species. We show that both genes have a conserved structure and expression, evidencing their role in sex determination, sex differentiation and the male reproductive cycle in A. altiparanae. These findings contribute to a better understanding of the molecular mechanisms of sex determination and differentiation in fish.
KW  - spermatogenesis
KW  - SOX9
KW  - DMRT1
KW  - sex differentiation
KW  - teleostei
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126486
VL  - 13
IS  - 2
ER  -