Robust Replication Control Is Generated by Temporal Gaps between Licensing and Firing Phases and Depends on Degradation of Firing Factor Sld2

Temporal separation of DNA replication initiation into licensing and firing phases ensures the precise duplication of the genome during each cell cycle. Cyclin-dependent kinase (CDK) is known to generate this separation by activating firing factors and at the same time inhibiting licensing factors but may not be sufficient to ensure robust separation at transitions between both phases. Here, we show that a temporal gap separates the inactivation of firing factors from the re-activation of licensing factors during mitosis in budding yeast. We find that gap size critically depends on phosphorylation-dependent degradation of the firing factor Sld2 mediated by CDK, DDK, Mck1, and Cdc5 kinases and the ubiquitin-ligases Dma1/2. Stable mutants of Sld2 minimize the gap and cause increased genome instability in an origin-dependent manner when combined with deregulation of other replication regulators or checkpoint mechanisms. Robust separation of licensing and firing phases therefore appears indispensable to safeguard genome stability

A CDK-regulated chromatin segregase promoting chromosome replication

The replication of chromosomes during S phase is critical for cellular and organismal function. Replicative stress can result in genome instability, which is a major driver of cancer. Yet how chromatin is made accessible during eukaryotic DNA synthesis is poorly understood. Here, we report the characterization of a chromatin remodeling enzyme-Yta7-entirely distinct from classical SNF2-ATPase family remodelers. Yta7 is a AAA+ -ATPase that assembles into \~1 MDa hexameric complexes capable of segregating histones from DNA. The Yta7 chromatin segregase promotes chromosome replication both in vivo and in vitro. Biochemical reconstitution experiments using purified proteins revealed that the enzymatic activity of Yta7 is regulated by S phase-forms of Cyclin-Dependent Kinase (S-CDK). S-CDK phosphorylation stimulates ATP hydrolysis by Yta7, promoting nucleosome disassembly and chromatin replication. Our results present a mechanism for how cells orchestrate chromatin dynamics in co-ordination with the cell cycle machinery to promote genome duplication during S phase

History and future of the scientific consensus on anthropogenic global warming

The article by Cook et al offers an interesting new methodological approach to the debate about (supposedly lacking) scientific consensus on global warming, showing that contrarian claims that there was no such consensus are clearly misleading. But once the attribution issue can be regarded as settled, new questions and controversies arise. They ultimately result from the different technological and organizational pathways towards a new global society model that takes its adverse climate change effects into account and seeks for new, but also risky solutions

Double Impact - The climate blockbuster 'The Day After Tomorrow' and its impact on the German cinema public

When The Day After Tomorrow was released by end of May 2004 in more than 80 countries world wide, a huge media debate was already underway, putting forward the pros and cons of the impact of a highly spectacular and fictitious disaster movie on the public. Many environmental activists and public agencies expected support for their issue, while many climate scientists remained more sceptical and even expected backlashes. A study by the Potsdam Institute for Climate Impact Research (PIK) in the framework of the European Climate Forum (ECF) tries to answer these and other questions. In six German cities a total of 1118 cinema visitors were asked before and after watching the film with regard to their perceptions of climate change, dangers associated with it, public and personal policy consequences, and film related issues. In addition, 149 telephone interviews were conducted with a subset of the sample about four weeks after the first two waves, controlling for persistency effects. The results show that the film surprised people by adding new, somewhat paradoxical features of climate change to the well established picture of slow and steady temperature increases with dangerous impacts distant in time and space. Climate change in the film is abrupt, close, and leads to a new ice age. People reacted with a drop in perceived probability of climate change. Nevertheless, the film did not lead to climate pessimism, but reinforced peoples' willingness to act, respectively to ask for political action. The film seems to have improved the public perception of science and the political role of scientists. The film might have opened a window of opportunity for (improved) environmental communication. (orig.)Available from TIB Hannover: RR5801(92) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Konzeptionelle Weiterentwicklung der Nachhaltigkeitsindikatoren zur Thematik Konsummuster - Kapitel 4 der Agenda 21. Langfassung

SIGLEAvailable from TIB Hannover: RN 8908(98-092) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekUmweltbundesamt, Berlin (Germany); Bundesministerium fuer Umwelt, Naturschutz und Reaktorsicherheit, Bonn (Germany)DEGerman

Lebensstile und globaler Energieverbrauch Analyse und Strategieansaetze zu einer nachhaltigen Energiestruktur

Lifestyle and consumption have emerged as research issues in energy and climate change related research in recent years for obvious reasons: with the emergence and the global spread of the modern 'consumer society' lifestyle induced consumption decisions by private households more and more influence total energy consumption and related carbon dioxide emissions. The paper discusses the use of the lifestyle concept derived from sociology and market research for household energy consumption and the potential for more sustainable changes. A main section is dedicated to a new way of decomposing country statistics on energy consumption, economic growth, CO_2 emissions, and energy mix. We detect five distinct patterns of national energy systems via a cluster analysis of country data and their change over time. These clusters represent distinct trajectories of the recent energy economic history of the country groups and define some path dependencies for energy policy options in the nearer future which are discussed briefly. The environmental kuznets curve (EKC) debate is discussed critically in the light of the more flexible and regionally adapted way of conceiving the worlds' energy system. The paper offers a quantitative the estimation of private households' contribution to total energy related CO_2 emissions, thus contributing to the assessment of lifestyle-related emissions. The final section discusses practical consequences for energy policy and lifestyle related environmental communication. (orig.)SIGLEAvailable from TIB Hannover: RR 5801(90) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

EUROPA - Modelling, Reflecting and Communicating Possible Futures of Europe in the Context of Global Change : Schlussbericht

[no abstract available

Strategien der Popularisierung des Leitbildes 'Nachhaltige Entwicklung' aus sozialwissenschaftlicher Perspektive Tagungsdokumentation. Bd. 1: Systematische Auswertung. Bd. 2: Tagungsbeitraege

Published in 2 separate volumesAvailable from TIB Hannover: RN 8908(2000,13,1): RN 8908(2000,13,2) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Umwelt, Naturschutz und Reaktorsicherheit, Bonn (Germany)DEGerman