What shaped the defense transformation policies of NATO member-states? And what does it mean for the future of the alliance? This dissertation explores the impact of the strategic cultures of the... Show moreWhat shaped the defense transformation policies of NATO member-states? And what does it mean for the future of the alliance? This dissertation explores the impact of the strategic cultures of the United States, the Netherlands and Germany on their efforts to adapt their defense policies and armed forces in light of significant changes in the security environment. Transformation was the central concept around which the Alliance was believed to find renewed cohesion. Instead, transformation in an era of expeditionary operations unearthed divergent views regarding the use of the military instrument. Each state pursued transformation differently and confronted different problems. These difficulties reflected the unique characteristics of their strategic culture. On the basis of the research it can be concluded that effective transformation can only take place when the characteristics of a state's strategic culture are taken into account. For NATO, it means that, unless the security environment changes substantially, friction within the alliance will persist and instead it will be necessary to work with these differences, rather than ignore them at its peril. Show less
The salicylic acid (SA) signaling pathway triggered by attack of biotrophic pathogens leads to broad spectrum resistance against a plethora of pathogenic fungi, bacteria and viruses and is known as... Show moreThe salicylic acid (SA) signaling pathway triggered by attack of biotrophic pathogens leads to broad spectrum resistance against a plethora of pathogenic fungi, bacteria and viruses and is known as systemic acquired resistance (SAR). One of the hallmarks of SAR is the accumulation of PR proteins and the induced expression of the PR-1 gene is often used as a marker for SAR. In this thesis we describe the characterization of a WRKY-class transcription factor (NtWRKY12) that specifically binds to the sequence TTTTCCAC. This sequence differs significantly from the consensus WRKY protein binding site TTGAC[C/T] (W-box), and was designated as the __WK-box__. The activation of PR-1a has always been proposed to occur mainly via TGA-factors. We show that NtWRKY12 can bind to TGA2.2 and has a more essential role in PR-1a activation. Using bioinformatic analysis various candidate genes have been prospected to have a role in regulation of the SA, jasmonate (JA) and ethylene (ET) biosynthesis or signaling pathways. The connection between AtWRKY28 and ICS1 was further studied. In protoplasts AtWRKY28 can activate ICS1 promoter::GUS reporter constructs and endogenous ICS1 mRNA levels. Using EMSA assays and ChIP experiments the bindingsite has been determined in vitro and confirmed in vivo. Show less
Plants defend themselves against stress, including pathogen or herbivore attack, via biosynthesis of defense proteins and of protective compounds called secondary metabolites. Stress induces these... Show morePlants defend themselves against stress, including pathogen or herbivore attack, via biosynthesis of defense proteins and of protective compounds called secondary metabolites. Stress induces these responses via a complex signal transduction network with jasmonic acid (JA) and related compounds as major players. In some defense responses JA acts synergistically with the stress hormone ethylene. It is largely unknown how JA induces expression of defense genes. It is also not well understood how the synergistic interaction between JA and ethylene is brought about. Previous research has identified several genes encoding AP2/ERF-domain transcription factors, called ORAs, whose expression is rapidly induced by JA in Arabidopsis. In this thesis, the function of several ORAs is addressed and shows that certain ORAs, by regulating the expression of defense-related genes, play major roles in JA signaling and defense. Show less