TY - JOUR A1 - Sanyal, D. A1 - Moriya, T. J. A1 - Langer, N. T1 - Envelope inflation in Wolf-Rayet stars and extended supernova shock breakout signals JF - Wolf-Rayet Stars : Proceedings of an International Workshop held in Potsdam, Germany, 1.–5. June 2015 N2 - Massive, luminous stars reaching the Eddington limit in their interiors develop very dilute, extended envelopes. This effect is called envelope inflation. If the progenitors of Type Ib/c supernovae, which are believed to be Wolf-Rayet (WR) stars, have inflated envelopes then the shock breakout signals diffuse in them and can extend their rise times significantly. We show that our inflated, hydrogen-free, WR stellar models with a radius of ∼R⊙ can have shock breakout signals longer than ∼ 60 s. The puzzlingly long shock breakout signal observed in the Type Ib SN 2008D can be explained by an inflated progenitor envelope, and more such events might argue in favour of existence of inflated envelopes in general. Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-88062 SP - 213 EP - 216 ER - TY - JOUR A1 - Jaeger-Erben, Melanie A1 - Spitzner, Meike A1 - Wustmans, Clemens A1 - Zeeb, Matthias T1 - Nachhaltige Grundsicherung BT - Antwort auf multiple Krisen? JF - Nachhaltige Grundsicherung: Armut überwinden – natürliche Lebensgrundlagen erhalten KW - Armut KW - Grundsicherung KW - Nachhaltigkeit KW - Ressourcen Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-81693 SN - 1868-6222 SN - 1868-6230 SP - 43 EP - 66 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - JOUR A1 - Bestenlehner, J. M. T1 - Stellar parameters from photometric data for fainter and more distant Wolf-Rayet stars JF - Wolf-Rayet Stars : Proceedings of an International Workshop held in Potsdam, Germany, 1.–5. June 2015 N2 - Spectroscopy is the preferred way to study the physical and wind properties of Wolf-Rayet (WR) stars, but with decreasing brightness and increasing distance of the object spectroscopy become very expensive. However, photometry still delivers a high signal to noise ratio. Current and past astronomical surveys and space missions provide large data sets, that can be harvested to discover new WR stars and study them over a wide metallicity range with the help of state of the art stellar atmosphere and evolutionary models. Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-88390 SP - 354 ER - TY - JOUR A1 - Crowther, P. A. T1 - Wolf-Rayet content of the Milky Way JF - Wolf-Rayet Stars : Proceedings of an International Workshop held in Potsdam, Germany, 1.–5. June 2015 N2 - An overview of the known Wolf-Rayet (WR) population of the Milky Way is presented, including a brief overview of historical catalogues and recent advances based on infrared photometric and spectroscopic observations resulting in the current census of 642 (vl.13 online catalogue). The observed distribution of WR stars is considered with respect to known star clusters, given that ≤20% of WR stars in the disk are located in clusters. WN stars outnumber WC stars at all galactocentric radii, while early-type WC stars are strongly biased against the inner Milky Way. Finally, recent estimates of the global WR population in the Milky Way are reassessed, with 1,200±100 estimated, such that the current census may be 50% complete. A characteristic WR lifetime of 0.25 Myr is inferred for an initial mass threshold of 25 M⊙. Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-87562 SP - 21 EP - 26 ER - TY - JOUR A1 - Weis, K. T1 - Family ties of WR to LBV nebulae yielding clues for stellar evolution JF - Wolf-Rayet Stars : Proceedings of an International Workshop held in Potsdam, Germany, 1.–5. June 2015 N2 - Luminous Blue Variables (LBVs) are stars is a transitional phase massive stars may enter while evolving from main-sequence to Wolf-Rayet stars. The to LBVs intrinsic photometric variability is based on the modulation of the stellar spectrum. Within a few years the spectrum shifts from OB to AF type and back. During their cool phase LBVs are close to the Humphreys-Davidson (equivalent to Eddington/Omega-Gamma) limit. LBVs have a rather high mass loss rate, with stellar winds that are fast in the hot and slower in the cool phase of an LBV. These alternating wind velocities lead to the formation of LBV nebulae by wind-wind interactions. A nebula can also be formed in a spontaneous giant eruption in which larger amounts of mass are ejected. LBV nebulae are generally small (< 5 pc) mainly gaseous circumstellar nebulae, with a rather large fraction of LBV nebulae being bipolar. After the LBV phase the star will turn into a Wolf-Rayet star, but note that not all WR stars need to have passed the LBV phase. Some follow from the RSG and the most massive directly from the MS phase. In general WRs have a large mass loss and really fast stellar winds. The WR wind may interact with winds of earlier phases (MS, RSG) to form WR nebulae. As for WR with LBV progenitors the scenario might be different, here no older wind is present but an LBV nebula! The nature of WR nebulae are therefore manifold and in particular the connection (or family ties) of WR to LBV nebulae is important to understand the transition between these two phases, the evolution of massive stars, their winds, wind-wind and wind-nebula interactions. Looking at the similarities and differences of LBV and WR nebula, figuring what is a genuine LBV and WR nebula are the basic question addressed in the analysis presented here. Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-87949 SP - 167 EP - 170 ER - TY - JOUR A1 - Steup, Martin T1 - Raum und Zahl in der Pflanzenphysiologie JF - Raum und Zahl Y1 - 2015 SN - 978-3-86464-082-7 SP - 77 EP - 109 PB - Trafo CY - Berlin ER - TY - JOUR A1 - Schwarte, Sandra A1 - Wegner, Fanny A1 - Havenstein, Katja A1 - Groth, Detlef A1 - Steup, Martin A1 - Tiedemann, Ralph T1 - Sequence variation, differential expression, and divergent evolution in starch-related genes among accessions of Arabidopsis thaliana JF - Plant molecular biology : an international journal of fundamental research and genetic engineering N2 - Transitory starch metabolism is a nonlinear and highly regulated process. It originated very early in the evolution of chloroplast-containing cells and is largely based on a mosaic of genes derived from either the eukaryotic host cell or the prokaryotic endosymbiont. Initially located in the cytoplasm, starch metabolism was rewired into plastids in Chloroplastida. Relocation was accompanied by gene duplications that occurred in most starch-related gene families and resulted in subfunctionalization of the respective gene products. Starch-related isozymes were then evolutionary conserved by constraints such as internal starch structure, posttranslational protein import into plastids and interactions with other starch-related proteins. 25 starch-related genes in 26 accessions of Arabidopsis thaliana were sequenced to assess intraspecific diversity, phylogenetic relationships, and modes of selection. Furthermore, sequences derived from additional 80 accessions that are publicly available were analyzed. Diversity varies significantly among the starch-related genes. Starch synthases and phosphorylases exhibit highest nucleotide diversities, while pyrophosphatases and debranching enzymes are most conserved. The gene trees are most compatible with a scenario of extensive recombination, perhaps in a Pleistocene refugium. Most genes are under purifying selection, but disruptive selection was inferred for a few genes/substitutiones. To study transcript levels, leaves were harvested throughout the light period. By quantifying the transcript levels and by analyzing the sequence of the respective accessions, we were able to estimate whether transcript levels are mainly determined by genetic (i.e., accession dependent) or physiological (i.e., time dependent) parameters. We also identified polymorphic sites that putatively affect pattern or the level of transcripts. KW - Arabidopsis thaliana KW - Divergent evolution KW - Intraspecific genetic variation KW - Positive selection KW - Starch metabolizing enzymes KW - Transcript levels Y1 - 2015 U6 - https://doi.org/10.1007/s11103-015-0293-2 SN - 0167-4412 SN - 1573-5028 VL - 87 IS - 4-5 SP - 489 EP - 519 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Rading, M. Michael A1 - Sandmann, Michael A1 - Steup, Martin A1 - Chiarugi, Davide A1 - Valleriani, Angelo T1 - Weak correlation of starch and volume in synchronized photosynthetic cells JF - Physical review : E, Statistical, nonlinear and soft matter physics N2 - In cultures of unicellular algae, features of single cells, such as cellular volume and starch content, are thought to be the result of carefully balanced growth and division processes. Single-cell analyses of synchronized photoautotrophic cultures of the unicellular alga Chlamydomonas reinhardtii reveal, however, that the cellular volume and starch content are only weakly correlated. Likewise, other cell parameters, e.g., the chlorophyll content per cell, are only weakly correlated with cell size. We derive the cell size distributions at the beginning of each synchronization cycle considering growth, timing of cell division and daughter cell release, and the uneven division of cell volume. Furthermore, we investigate the link between cell volume growth and starch accumulation. This work presents evidence that, under the experimental conditions of light-dark synchronized cultures, the weak correlation between both cell features is a result of a cumulative process rather than due to asymmetric partition of biomolecules during cell division. This cumulative process necessarily limits cellular similarities within a synchronized cell population. Y1 - 2015 U6 - https://doi.org/10.1103/PhysRevE.91.012711 SN - 1539-3755 SN - 1550-2376 VL - 91 IS - 1 PB - American Physical Society CY - College Park ER - TY - JOUR A1 - Cisek, Richard A1 - Tokarz, Danielle A1 - Steup, Martin A1 - Tetlow, Ian J. A1 - Emes, Michael J. A1 - Hebelstrup, Kim H. A1 - Blennow, Andreas A1 - Barzda, Virginijus T1 - Second harmonic generation microscopy investigation of the crystalline ultrastructure of three barley starch lines affected by hydration JF - Biomedical optics express N2 - Second harmonic generation (SHG) microscopy is employed to study changes in crystalline organization due to altered gene expression and hydration in barley starch granules. SHG intensity and susceptibility ratio values (R'(SHG)) are obtained using reduced Stokes-Mueller polarimetric microscopy. The maximum R'(SHG) values occur at moderate moisture indicating the narrowest orientation distribution of nonlinear dipoles from the cylindrical axis of glucan helices. The maximum SHG intensity occurs at the highest moisture and amylopectin content. These results support the hypothesis that SHG is caused by ordered hydrogen and hydroxyl bond networks which increase with hydration of starch granules. (C) 2015 Optical Society of America Y1 - 2015 U6 - https://doi.org/10.1364/BOE.6.003694 SN - 2156-7085 VL - 6 IS - 10 SP - 3694 EP - 3700 PB - Optical Society of America CY - Washington ER - TY - JOUR A1 - Ette, Ottmar T1 - Excellence(s), velociferina(s). On the bestiary of deceptive elites of Bologna JF - Literatura : teoría, historia, crítica ; revista del Departamento de Literatura Y1 - 2015 SN - 0123-5931 SN - 2256-5450 VL - 17 IS - 2 SP - 237 EP - 242 PB - Departamento de Literatura, Universidad Nacional de Colombia CY - Bogota ER - TY - JOUR A1 - Wacker, Alexander A1 - Piepho, Maike A1 - Spijkerman, Elly T1 - Photosynthetic and fatty acid acclimation of four phytoplankton species in response to light intensity and phosphorus availability JF - European journal of phycology N2 - Photosynthetic acclimation of phytoplankton to lower irradiation can be met by several strategies such as increasing the affinity for light or increasing antenna size and stacking of the thylakoids. The latter is reflected by a higher proportion of polyunsaturated fatty acids (PUFAs). Additionally, photosynthetic capacity (P-max), respiratory losses, and proton leakage can be reduced under low light. Here we consider the effect of light intensity and phosphorus availability simultaneously on the photosynthetic acclimation and fatty acid composition of four phytoplankters. We studied representatives of the Chlorophyceae, Cryptophyceae and Mediophyceae, all of which are important components of plankton communities in temperate lakes. In our analysis, excluding fatty acid composition, we found different acclimation strategies in the chlorophytes Scenedesmus quadricauda, Chlamydomonas globosa, cryptophyte Cryptomonas ovata and ochrophyte Cyclotella meneghiniana. We observed interactive effects of light and phosphorus conditions on photosynthetic capacity in S. quadricauda and Cry. ovata. Cry. ovata can be characterized as a low light-acclimated species, whereas S. quadricauda and Cyc. meneghiniana can cope best with a combination of high light intensities and low phosphorus supply. Principal component analyses (PCA), including fatty acid composition, showed further species-specific patterns in their regulation of P-max with PUFAs and light. In S. quadricauda and Cyc. meneghiniana, PUFAs negatively affected the relationship between P-max and light. In Chl. globosa, lower light coincided with higher PUFAs and lower P-max, but PCA also indicated that PUFAs had no direct influence on P-max. PUFAs and P-max were unaffected by light in Cry. ovata. We did not observe a general trend in the four species tested and concluded that, in particular, the interactive effects highlight the importance of taking into account more than one environmental factor when assessing photosynthetic acclimation to lower irradiation. KW - chlorophyll content KW - dark respiration KW - FAME KW - light acclimation KW - oxygen evolution KW - photosynthesis KW - phytoplankton KW - polyunsaturated fatty acids Y1 - 2015 U6 - https://doi.org/10.1080/09670262.2015.1050068 SN - 0967-0262 SN - 1469-4433 VL - 50 IS - 3 SP - 288 EP - 300 PB - Routledge, Taylor & Francis Group CY - Abingdon ER - TY - JOUR A1 - Sperfeld, Erik A1 - Wacker, Alexander T1 - Maternal diet of Daphnia magna affects offspring growth responses to supplementation with particular polyunsaturated fatty acids JF - Hydrobiologia : acta hydrobiologica, hydrographica, limnologica et protistologica N2 - Previous studies examining the effects of food quality on zooplankton often controlled for maternal effects of resource provisioning using standardized maternal diets. However, varying nutritional history of mothers may change resource provisioning to their progeny, especially regarding polyunsaturated fatty acids (PUFAs), which may change the interpretation of previously observed fitness responses of offspring. To assess PUFA-mediated maternal provisioning effects on offspring, we raised females of the cladoceran Daphnia magna on diets differing considerably in PUFA composition and raised their offspring on a PUFA-lacking diet supplemented with the omega 3 PUFAs alpha-linolenic acid (ALA) and/or eicosapentaenoic acid (EPA). The mass-specific growth responses of offspring to their own diets were affected by the maternal diet regime, probably due to varying maternal PUFA provisioning. A low maternal provisioning of EPA or ALA was sufficient to prevent growth limitation of offspring by these PUFAs until reaching maturity. A comparison with results of published ALA and EPA supplementation experiments suggests that the previously observed limitation effects depended on the usage of a single algae genus as maternal diet. Therefore, we suggest that maternal diets should be deliberately varied in future studies assessing ecological relevant food quality effects on zooplankton, especially regarding PUFAs. KW - Food quality KW - Maternal effects KW - Nutritional ecology KW - Resource provisioning KW - Zooplankton Y1 - 2015 U6 - https://doi.org/10.1007/s10750-015-2244-y SN - 0018-8158 SN - 1573-5117 VL - 755 IS - 1 SP - 267 EP - 282 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Wacker, Alexander A1 - Marzetz, Vanessa A1 - Spijkerman, Elly T1 - Interspecific competition in phytoplankton drives the availability of essential mineral and biochemical nutrients JF - Ecology : a publication of the Ecological Society of America N2 - The underlying mechanisms and consequences of competition and diversity are central themes in ecology. A higher diversity of primary producers often results in higher resource use efficiency in aquatic and terrestrial ecosystems. This may result in more food for consumers on one hand, while, on the other hand, it can also result in a decreased food quality for consumers; higher biomass combined with the same availability of the limiting compound directly reduces the dietary proportion of the limiting compound. Here we tested whether and how interspecific competition in phytoplankton communities leads to changes in resource use efficiency and cellular concentrations of nutrients and fatty acids. The measured particulate carbon : phosphorus ratios (C:P) and fatty acid concentrations in the communities were compared to the theoretically expected ratios and concentrations of measurements on simultaneously running monocultures. With interspecific competition, phytoplankton communities had higher concentrations of the monounsaturated fatty acid oleic acid and also much higher concentrations of the ecologically and physiologically relevant long-chain polyunsaturated fatty acid eicosapentaenoic acid than expected concentrations based on monocultures. Such higher availability of essential fatty acids may contribute to the positive relationship between phytoplankton diversity and zooplankton growth, and may compensate limitations by mineral nutrients in higher trophic levels. KW - biodiversity KW - C:P ratio KW - competition KW - eicosapentaenoic acid KW - elemental composition KW - EPA KW - food quality KW - minerals KW - phosphorus KW - polyunsaturated fatty acids KW - PUFA KW - resource use efficiency Y1 - 2015 U6 - https://doi.org/10.1890/14-1915.1 SN - 0012-9658 SN - 1939-9170 VL - 96 IS - 9 SP - 2467 EP - 2477 PB - Wiley CY - Washington ER - TY - JOUR A1 - Schwarzenberger, Anke A1 - Wacker, Alexander T1 - Melatonin synthesis follows a daily cycle in Daphnia JF - Journal of plankton research N2 - In freshwater systems, Daphnia has been demonstrated to show adaptive responses following the light-dark cycle. The adjustment of these responses to the change of day and night is probably transmitted via the hormone melatonin. The rate-limiting enzyme in melatonin synthesis is the arylalkylamine N-transferase (AANAT). We identified three genes coding for insect-like AANATs in Daphnia, of which we measured the gene expression in an ecologically relevant light-dark cycle. We demonstrated that Daphnia's insect-like AANAT gene expression oscillated in a daily manner, and that the highest peak of expression after the onset of darkness was followed by a peak of melatonin production at midnight. Moreover, we could show an oscillation of endogenous melatonin synthesis in Daphnia. In most organisms, melatonin synthesis is due to rhythmic expression of genes of the circadian clock, since transcription of aanats is directly linked to a circadian transcription factor. We could demonstrate that putative clock genes and insect-like AANAT genes of Daphnia were equally expressed. Therefore, we propose that melatonin synthesis is coupled to the expression of Daphnia clock genes, and that insect-like AANATs of crustaceans have a similar function as AANATs of vertebrates: The initiation of melatonin synthesis. In future studies with Daphnia, it will be necessary to take the time of day into account since melatonin concentrations might influence stress responses. KW - arylalkylamine N-transferase KW - insect-like AANAT KW - qPCR KW - circadian clock KW - clock genes Y1 - 2015 U6 - https://doi.org/10.1093/plankt/fbv029 SN - 0142-7873 SN - 1464-3774 VL - 37 IS - 3 SP - 636 EP - 644 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Zimmermann, Andreas A1 - Ney, Martin T1 - Cyber-Security beyond the military perspective: International Law 'cyber space' and the concept of due diligence. JF - German Yearbook of International Law Y1 - 2015 VL - 58 SP - 51 EP - 66 PB - Duncker & Humblot CY - Berlin ER - TY - JOUR A1 - Zimmermann, Andreas T1 - The Palestinian-Israeli Conflict: Developing International Law Without Solving the Conflict JF - Archiv des Völkerrechts N2 - The article analyses whether the Palestinian-Israeli conflict has served as a catalyst for the development of international law, as well as whether international law has been instrumental in attempting to find solutions for the said conflict. In several ways, this conflict has made a significant contribution to understanding and interpreting the UN Charter. It also brought along important developments about the role of third parties, both under the Geneva Conventions and under the law of state responsibility, which provides for an obligation of not recognizing as legal, or not rendering aid or assistance to situations caused by serious violations of jus cogens. International judicial institutions (and also domestic ones) play a rather limited role in this respect, due both to a lack of courage to address fundamental questions, and/or a disregard of the outcome of the proceedings by at least one of the parties to the conflict. Other reasons are Israel's reluctance of accepting the jurisdiction of either the ICJ or the ICC, and its view on the non-applicability of human rights treaties outside of its territory, as well as Palestine's uncertain status in the international community limiting its access to international courts. However, the ICJ's 2004 (formally non-binding) advisory opinion on the Israeli Wall provided answers to some of the most fundamental questions related to the conflict, unfortunately without having any immediate impact on the situation on the ground. Given Palestine's accession to the Rome Statute in early 2015, time has yet to show which role in the process will be played by the ICC. Other issues arising from the conflict, and examined by this article, are that of (Palestinian) statehood, going beyond the traditional concept of statehood and including the consequences of the jus cogens-character of the right of self-determination, as well as questions of treaty succession and succession in matters of State responsibility with regard to acts committed by the PLO. Y1 - 2015 U6 - https://doi.org/10.1628/000389215X14412717564749 VL - 53 IS - 2 SP - 149 EP - 166 PB - Mohr Siebeck CY - Tübingen ER - TY - JOUR A1 - Megow, Jörg A1 - Körzdörfer, Thomas A1 - Renger, Thomas A1 - Sparenberg, Mino A1 - Blumstengel, Sylke A1 - Henneberger, Fritz A1 - May, Volkhard T1 - Calculating Optical Absorption Spectra of Thin Polycrystalline Organic Films: Structural Disorder and Site-Dependent van der Waals Interaction JF - The journal of physical chemistry : C, Nanomaterials and interfaces N2 - We propose a new approach for calculating the change of the absorption spectrum of a molecule when moved from the gas phase to a crystalline morphology. The so-called gas-to-crystal shift Delta epsilon(m) is mainly caused by dispersion effects and depends sensitively on the molecules specific position in the nanoscopic setting. Using an extended dipole approximation, we are able to divide Delta epsilon(m)= -QW(m) in two factors, where Q depends only on the molecular species and accounts for all nonresonant electronic transitions contributing to the dispersion while W-m is a geometry factor expressing the site dependence of the shift in a given molecular structure. The ability of our approach to predict absorption spectra is demonstrated using the example of polycrystalline films of 3,4,9,10-perylenetetracarboxylic diimide (PTCDI). Y1 - 2015 U6 - https://doi.org/10.1021/acs.jpcc.5b01587 SN - 1932-7447 VL - 119 IS - 10 SP - 5747 EP - 5751 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Egbert, Björn A1 - Giest, Hartmut ED - Meier, Bernd ED - Banse, Gerhard T1 - Lernen ohne Anschluss BT - die Fächer Sachunterricht und Wirtschaft-Arbeit-Technik in der Anhörungsfassung des Rahmenlehrplanes für die Länder Berlin und Brandenburg JF - Allgemeinbildung und Curriculumentwicklung : Herrausforderung an das Fach Wirtschaft - Arbeit - Technik Y1 - 2015 SN - 978-3-631-66541-1 SP - 147 EP - 163 PB - Lang CY - Berlin ER - TY - JOUR A1 - Renz, Marc A1 - Otten, Cecile A1 - Faurobert, Eva A1 - Rudolph, Franziska A1 - Zhu, Yuan A1 - Boulday, Gwenola A1 - Duchene, Johan A1 - Mickoleit, Michaela A1 - Dietrich, Ann-Christin A1 - Ramspacher, Caroline A1 - Steed, Emily A1 - Manet-Dupe, Sandra A1 - Benz, Alexander A1 - Hassel, David A1 - Vermot, Julien A1 - Huisken, Jan A1 - Tournier-Lasserve, Elisabeth A1 - Felbor, Ute A1 - Sure, Ulrich A1 - Albiges-Rizo, Corinne A1 - Abdelilah-Seyfried, Salim T1 - Regulation of beta 1 Integrin-Klf2-Mediated angiogenesis by CCM proteins JF - Developmental cell N2 - Mechanotransduction pathways are activated in response to biophysical stimuli during the development or homeostasis of organs and tissues. In zebrafish, the blood-flow-sensitive transcription factor Klf2a promotes VEGF-dependent angiogenesis. However, the means by which the Klf2a mechanotransduction pathway is regulated to prevent continuous angiogenesis remain unknown. Here we report that the upregulation of klf2 mRNA causes enhanced egfl7 expression and angiogenesis signaling, which underlies cardiovascular defects associated with the loss of cerebral cavernous malformation (CCM) proteins in the zebrafish embryo. Using CCM-protein-depleted human umbilical vein endothelial cells, we show that the misexpression of KLF2 mRNA requires the extracellular matrix-binding receptor beta 1 integrin and occurs in the absence of blood flow. Downregulation of beta 1 integrin rescues ccm mutant cardiovascular malformations in zebrafish. Our work reveals a beta 1 integrin-Klf2-Egfl7-signaling pathway that is tightly regulated by CCM proteins. This regulation prevents angiogenic overgrowth and ensures the quiescence of endothelial cells. Y1 - 2015 U6 - https://doi.org/10.1016/j.devcel.2014.12.016 SN - 1534-5807 SN - 1878-1551 VL - 32 IS - 2 SP - 181 EP - 190 PB - Cell Press CY - Cambridge ER - TY - JOUR A1 - Lombardo, Veronica A. A1 - Otten, Cecile A1 - Abdelilah-Seyfried, Salim T1 - Large-scale Zebrafish Embryonic Heart Dissection for Transcriptional Analysis JF - Journal of visualized experiments N2 - The zebrafish embryonic heart is composed of only a few hundred cells, representing only a small fraction of the entire embryo. Therefore, to prevent the cardiac transcriptome from being masked by the global embryonic transcriptome, it is necessary to collect sufficient numbers of hearts for further analyses. Furthermore, as zebrafish cardiac development proceeds rapidly, heart collection and RNA extraction methods need to be quick in order to ensure homogeneity of the samples. Here, we present a rapid manual dissection protocol for collecting functional/beating hearts from zebrafish embryos. This is an essential prerequisite for subsequent cardiac-specific RNA extraction to determine cardiac-specific gene expression levels by transcriptome analyses, such as quantitative real-time polymerase chain reaction (RT-qPCR). The method is based on differential adhesive properties of the zebrafish embryonic heart compared with other tissues; this allows for the rapid physical separation of cardiac from extracardiac tissue by a combination of fluidic shear force disruption, stepwise filtration and manual collection of transgenic fluorescently labeled hearts. KW - Developmental Biology KW - Issue 95 KW - zebrafish KW - embryo KW - heart KW - dissection KW - RNA KW - RT-qPCR Y1 - 2015 U6 - https://doi.org/10.3791/52087 SN - 1940-087X IS - 95 PB - JoVE CY - Cambridge ER -