50 research outputs found
Teilstationäre Hochwasserschutzmaßnahmen als kurzfristige Strategie zum Schutz der nordfriesischen Halligen – Einsatztests unter praxisnahen Bedingungen und Berücksichtigung sozialer Bedürfnisse der Bewohner*innen
Online First, geplanter Druck 202
Mitotic activity patterns and cytoskeletal changes throughout the progression of diapause developmental program in Daphnia
Abstract Background Diapause is a form of dormancy that is genetically predetermined to allow animals to overcome harsh environmental conditions. It is induced by predictive environmental cues bringing cellular activity levels into a state of suspended animation. Entering diapause requires organismal, molecular and cellular adaptation to severely reduced energy flows. Cells must therefore have evolved strategies that prepare them for periods with limited metabolic resources. However, changes that occur on the (sub-)cellular level have not been thoroughly described. Results We investigated mitotic activity and we monitored cytoskeletal network changes in successive stages of diapausing and non-diapausing Daphnia magna embryos using (immuno-)fluorescent labeling. We find that embryos destined to diapause show a delayed and 2.5x slower mitotic activity in comparison to continuously developing embryos. Development is halted when D. magna embryos reach ~ 3500 cells, whereupon mitotic activity is absent and cytoskeletal components are severely reduced, rendering diapause cells compact and condensed. Conclusion In the initiation phase of diapause, the slower cell division rate points to prolonged interphase duration, preparing the cells for diapause maintenance. During diapause, cytoskeletal depletion and cellular condensation may be a means to save energy resources. Our data provide insights into the sub-cellular change of diapause in Daphnia
Adjuvant formulated virus-like particles expressing native-like forms of the Lassa virus envelope surface glycoprotein are immunogenic and induce antibodies with broadly neutralizing activity
Lassa mammarenavirus (LASV) is a rodent-borne arenavirus endemic to several West African countries. It is the causative agent of human Lassa fever, an acute viral hemorrhagic fever disease. To date, no therapeutics or vaccines against LASV have obtained regulatory approval. Polyclonal neutralizing antibodies derived from hyperimmunized animals may offer a useful strategy for prophylactic and therapeutic intervention to combat human LASV infections. The LASV envelope surface glycoprotein complex (GP) is the major target for neutralizing antibodies, and it is the main viral antigen used for the design of an LASV vaccine. Here, we assessed the immunogenic potential of mammalian cell-derived virus-like particles (VLPs) expressing GP from the prototypic LASV strain Josiah in a native-like conformation as the sole viral antigen. We demonstrate that an adjuvanted prime-boost immunization regimen with GP-derived VLPs elicited neutralizing antibody responses in rabbits, suggesting that effective antigenic epitopes of GP were displayed. Notably, these antibodies exhibited broad reactivity across five genetic lineages of LASV. VLP-based immunization strategies may represent a powerful approach for generating polyclonal sera containing cross-reactive neutralizing antibodies against LASV
Protein phosphorylation and its role in archaeal signal transduction
Reversible protein phosphorylation is the main mechanism of signal transduction that enables cells to rapidly respond to
environmental changes by controlling the functional properties of proteins in response to external stimuli. However,
whereas signal transduction is well studied in Eukaryotes and Bacteria, the knowledge in Archaea is still rather scarce.
Archaea are special with regard to protein phosphorylation, due to the fact that the two best studied phyla, the
Euryarchaeota and Crenarchaeaota, seem to exhibit fundamental differences in regulatory systems. Euryarchaeota (e.g.
halophiles, methanogens, thermophiles), like Bacteria and Eukaryotes, rely on bacterial-type two-component signal
transduction systems (phosphorylation on His and Asp), as well as on the protein phosphorylation on Ser, Thr and Tyr by
Hanks-type protein kinases. Instead, Crenarchaeota (e.g. acidophiles and (hyper)thermophiles) only depend on Hanks-type
protein phosphorylation. In this review, the current knowledge of reversible protein phosphorylation in Archaea is
presented. It combines results from identified phosphoproteins, biochemical characterization of protein kinases and
protein phosphatases as well as target enzymes and first insights into archaeal signal transduction by biochemical, genetic and polyomic studie
Praxisnahes Küstenlabor zur Entwicklung von kurz- und langfristigen Strategien zum Schutz und zur Bewahrung der schleswig-holsteinischen Halligen (Living CoastLab Halligen)
Online First, geplanter Druck 202
Geographical and temporal distribution of SARS-CoV-2 clades in the WHO European Region, January to June 2020
We show the distribution of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) genetic clades over time and between countries and outline potential genomic surveillance objectives. We applied three genomic nomenclature systems to all sequence data from the World Health Organization European Region available until 10 July 2020. We highlight the importance of real-time sequencing and data dissemination in a pandemic situation, compare the nomenclatures and lay a foundation for future European genomic surveillance of SARS-CoV-2