7 research outputs found
Rev Proteins of Human and Simian Immunodeficiency Virus Enhance RNA Encapsidation
The main function attributed to the Rev proteins of immunodeficiency viruses is the shuttling of viral RNAs containing the Rev responsive element (RRE) via the CRM-1 export pathway from the nucleus to the cytoplasm. This restricts expression of structural proteins to the late phase of the lentiviral replication cycle. Using Rev-independent gag-pol expression plasmids of HIV-1 and simian immunodeficiency virus and lentiviral vector constructs, we have observed that HIV-1 and simian immunodeficiency virus Rev enhanced RNA encapsidation 20- to 70-fold, correlating well with the effect of Rev on vector titers. In contrast, cytoplasmic vector RNA levels were only marginally affected by Rev. Binding of Rev to the RRE or to a heterologous RNA element was required for Rev-mediated enhancement of RNA encapsidation. In addition to specific interactions of nucleocapsid with the packaging signal at the 5′ end of the genome, the Rev/RRE system provides a second mechanism contributing to preferential encapsidation of genomic lentiviral RNA
The new COSYNA Underwater Node System – a transregional and transinstitutional research approach in the North Sea and in the Arctic
Coastal ecosystems are important interface zones between the terrestrial and the marine realm. Due to the continuously increasing anthropogenic pressure on most coastlines worldwide, a significant increase in the effort to monitor and assess changes in the coastal systems has been proposed. In the framework of COSYNA (Coastal Observation System of the Northern and Artic Seas), a cable connected underwater observatory for long term exposure even under extreme environmental conditions has been developed. Two prototypes of the COSYNA underwater node system have been installed in 2012 in the southern North Sea and in an Artic Fjord System (Kongsfjord Svalbard) and are operated since then continuously. These systems provide the logistic underwater platforms to operate standard sensors like ADCP and CTD as well as complex sensors like a continuous plankton recorder or a stereo-optical fish detection device with a data transmission rate up to 1 GHz year in both ecosystems.
The main scientific objective of the COSYNA underwater node technology is the continuous assessment and (near) real time analysis of environmental parameters in the COSYNA target environments the North Sea and the Arctic Sea. The continuous data stream of the main oceanographic, hydraulic and biological parameters sampled synchronously in the two ecosystems year round even under extreme conditions like severe storms in the North Sea or ice coverage in the Arctic are used to monitor, analyse and to model ecosystem behaviour with respect to abiotic environmental dynamics and environmental shifts
COSYNA - Unterwasserknoten. Die neue Infrastruktur für Nordsee und Arktis
Küsten stellen Schnittstelle des Menschen zum Meer dar und sind durch vielfältige Nutzung, Klimawandel und Meeres- spiegelanstieg zunehmend betroffen. Veränderungen in der Frequenz und Stärke von Starkwind- und Sturmereignissen und deren Bedeutung für die Küstengebiete werden in diesem Zusammenhang intensiv diskutiert. Im Rahmen von COSYNA werden seit 2011 verkabelte Unterwasserknoten für flache Schelfmeere entwickelt. Sie stellen eine zentrale Technologie für ein effizientes und wetterunabhängiges Küstenmonitoring und eine daraus aufgebaute ereignisgestützte Forschung dar.
Ziel der Unterwasserknoten in der Nordsee und dem Polarmeer ist:
• die hoch auflösende Erfassung vielfältiger Umweltparameter in Echtzeit, auch unter extremen Umweltbedingungen (Sturm, Kälte), um deren Dynamik auf täglicher, saisonaler und klimarelevanten Zeitskalen zu erfassen und besser zu verstehen.
• die Unterscheidung natürlicher Variabilität (systemabhängige/ lokale sowie systemunabhängige/potentiell allgemeingültige Prozesse) von Klimaerwärmung oder lokalen anthropogenen Einflüssen.
• die Abschätzung der Auswirkung von Extremereignissen (Stürme)
A multi-proxy investigation of sediment core GeoB7165-1 and AMS 14C dating points from sediment cores off Conceptión (~ 36°S)
A high-resolution sea surface temperature and paleoproductivity reconstruction on a sedimentary record collected at 36°S off central-south Chile (GeoB 7165-1, 36°33'S, 73°40'W, 797 m water depth, core length 750 cm) indicates that paleoceanographic conditions changed abruptly between 18 and 17 ka. Comparative analysis of several cores along the Chilean continental margin (30°-41°S) suggests that the onset and the pattern of deglacial warming was not uniform off central-south Chile due to the progressive southward migration of the Southern Westerlies and local variations in upwelling. Marine productivity augmented rather abruptly at 13-14 ka, well after the oceanographic changes.We suggest that the late deglacial increase in paleoproductivity off central-south Chile reflects the onset of an active upwelling system bringing nutrient-rich, oxygen-poor Equatorial SubsurfaceWater to the euphotic zone, and a relatively higher nutrient load of the Antarctic Circumpolar Current. During the Last Glacial Maximum, when the Southern Westerlies were located further north, productivity off central-south Chile, in contrast to off northern Chile, was reduced due to direct onshore-blowing winds that prevented coastal upwelling and export production
Rev proteins of human and simian immunodeficiency virus enhance RNA encapsidation
The main function attributed to the Rev proteins of immunodeficiency viruses is the shuttling of viral RNAs containing the Rev responsive element (RRE) via the CRM-1 export pathway from the nucleus to the cytoplasm. This restricts expression of structural proteins to the late phase of the lentiviral replication cycle. Using Rev-independent expression plasmids of HIV-1 and simian immunodeficiency virus and lentiviral vector constructs, we have observed that HIV-1 and simian immunodeficiency virus Rev enhanced RNA encapsidation 20- to 70-fold, correlating well with the effect of Rev on vector titers. In contrast, cytoplasmic vector RNA levels were only marginally affected by Rev. Binding of Rev to the RRE or to a heterologous RNA element was required for Rev-mediated enhancement of RNA encapsidation. In addition to specific interactions of nucleocapsid with the packaging signal at the 5' end of the genome, the Rev/RRE system provides a second mechanism contributing to preferential encapsidation of genomic lentiviral RNA