Norway's international development assistance policy in the current international environment: mechanisms of justification

This article addresses the basic mechanisms of Norway's current Development Assistance policy. The author analyses the strengthening of the financial policy and principal mechanisms for justifying Norway's participation in the ODA as well as the country's foreign policy objectives attained through assistance. The article examines specific features of Norway's development policy, which are crucial to understand contemporary international aid practices. The country's development policy implemented bilaterally and multilaterally is an effective mechanism of promoting Norway's economic and political interests. It is also an important subject for research. The authors analyses the evolution of the ODA objectives, its institutions and their international expertise. Special attention is devoted to the current shift of the ODA policy to the issues of its effectiveness. The recent shift to social cooperation development by involving NGOs and private businesses and investing in the social sphere is also examined. The a rticle analyses Norway's official position on humanitarian assistance in crises and armed conflicts. The author examines a number of cases of Norway's International Development Assistance policy

Aberrant growth and lethality of Arabidopsis deficient in nonsense-mediated RNA decay factors is caused by autoimmune-like response

Nonsense-mediated RNA decay (NMD) is an evolutionarily conserved RNA quality control mechanism that eliminates transcripts containing nonsense mutations. NMD has also been shown to affect the expression of numerous genes, and inactivation of this pathway is lethal in higher eukaryotes. However, despite relatively detailed knowledge of the molecular basis of NMD, our understanding of its physiological functions is still limited and the underlying causes of lethality are unknown. In this study, we examined the importance of NMD in plants by analyzing an allelic series of Arabidopsis thaliana mutants impaired in the core NMD components SMG7 and UPF1. We found that impaired NMD elicits a pathogen defense response which appears to be proportional to the extent of NMD deficiency. We also demonstrate that developmental aberrations and lethality of the strong smg7 and upf1 alleles are caused by constitutive pathogen response upregulation. Disruption of pathogen signaling suppresses the lethality of the upf1-3 null allele and growth defects associated with SMG7 dysfunction. Interestingly, infertility and abortive meiosis observed in smg7 mutants is not coupled with impaired NMD suggesting a broader function of SMG7 in cellular metabolism. Taken together, our results uncover a major physiological consequence of NMD deficiency in Arabidopsis and revealed multifaceted roles of SMG7 in plant growth and development

Regulation of meiotic progression in Arabidopsis

Meiose, eine spezielle Art der Zellteilung, ist für die sexuelle Reproduktion notwendig. Obwohl die regulatorischen Mechanismen ähnlich jenen der Mitose sind, hat Meiose einige entscheidende Unterschiede in dessen Regulierung. In Mitose findet DNA Replikation immer vor der Zellteilung statt. In Meiose durchläuft eine diploide Mutterzelle eine zweifache Chromosomensegregation ohne vorheriger DNA Synthese, was in vier haploiden Tochterzellen resultiert. Die Zellzyklusmaschinerie muss so modifiziert werden, dass die DNA Replikation nach Meiose I unterdrückt wird, was durch ein erhöhtes Level an cyclin-dependent kinase (cdk) Aktivität erzielt wird. Nach der zweiten nuklearenTeilung muss eine komplette cdk Inaktivierung erfolgen, um die Meiose zu beenden. Die Mechanismen der unterschiedlichen Regulierung von cdk nach der 1. und 2. meiotischen Teilung sind noch unklar. Um die Regulierung der Meiose in Pflanzen besser zu verstehen, war ein Ziel meines Dokorrats die Charakterisierung des SMG7 Genes, welches für den Meioseaustritt essenziell ist. Ich habe eine zytogenetische Methode entwickelt, die das Aktivitätslevel von cdk in verschiedenen meiotischen Phasen bestimmt und zeigte, dass der Defekt in smg7 Mutanten auf einer mangelnden Herunterregulierung der cdk Aktivität bei Meioseaustritt basiert. Ich testete ob die Inaktivierung eines meiotischen Zyklins den Anaphase II Arrest in smg7 Mutanten verringert. TAM ist ein A-Typ Zyklin, das während Meiose I exprimiert wird und dessen Fehlen zu einem verfrühten Meioseaustritt in Interkinese führt. Ich konnte zeigen, dass dieser tam Phenotyp durch die Inaktivierung von SMG7 unterdrückt wird. Ein weiteres Protein das für den Meioseaustritt wichtig ist, ist TDM1 und ich demonstrierte, dass der Anaphase II Arrest der smg7 Mutanten von TDM1 abhängt. Außerdem ist TDM1 epistatisch zu TAM. Dies weist darauf hin, dass TAM für den Eintritt in Meiose II entscheidend ist, aber für den Verlauf der Meiose II andere cdk-Zyklin Komlexe verantwortlich sind. Im zweiten Teil meines Projektes fokussierte ich auf die Identifikation von Zyklinen, die während der männlichen Meiose in Arabidopsis exprimiert werden. Ich entwickelte Markerlinien für alle 11 Arabidopsis B-Typ Zykline und zeigte, dass drei Linien in Meiose exprimiert werden. Weitere Analysen weisen darauf hin, dass zwei Zykline unkonservierte Pseudogene sind. Zurzeit untersuche ich, ob das einzige konservierte Protein-kodierende Zyklin für eine Restaktivität der cdk in der Interkinese verantwortlich ist und ob SMG7 in der Regulierung dieser Aktivität beteiligt ist.Meiosis is a specialized cell division necessary for sexual reproduction. Although the fundamental regulatory mechanisms are shared with mitosis, meiosis has several crucial characteristics that require a different regulation. Whereas in mitotic cell cycle is cell division always preceded by DNA replication, during meiosis a diploid maternal cell undergoes two subsequent rounds of chromosome segregation in the absence of DNA synthesis, which results in formation of four haploid daughter cells. Therefore the cell cycle machinery has to be modified to repress DNA replication after the first meiotic division. This is achieved by mechanisms that retain elevated levels of cyclin-dependent kinase (cdk) activity after meiosis I. However, complete cdk inactivation must occur after the second nuclear division to allow for exit from meiosis. Mechanisms that govern the differential regulation of transition from high to low cdk activity after the first and second meiotic divisions are still poorly understood. To understand regulation of meiotic cell cycle in plants, one aim of my thesis was focused on characterization of the SMG7 gene that is essential for meiotic exit. I developed a cytogenetic method to study the level of cdk activity in distinct stages of meiosis and I could show that the defect in smg7 mutants is caused by a failure to downregulate cdk activity at meiotic exit. Therefore I tested whether inactivation of a meiotic cyclin alleviates anaphase II arrest in SMG7 deficient plants. TAM is an A-type cyclin, that is specifically expressed during first meiotic division and its deficiency causes premature exit from meiosis in interkinesis. Interestingly, I found that the tam phenotype is suppressed by inactivation of SMG7. Another protein important for meiotic exit is TDM1. I showed that the anaphase II arrest observed in smg7 mutants is dependent on TDM1. In addition, TDM1 is also epistatic to TAM. These data argue that while TAM is crucial for entry into the second meiotic division, progression through meiosis II has to be driven by another cdk-cyclin complex(es). To determine the core meiotic cell cycle machinery I focused the second part of my project on the identification of cyclins expressed during male meiosis in Arabidopsis. I generated marker lines for all 11 Arabidopsis B-type cyclins and found that three of them are expressed during meiosis. Further analysis indicated that two cyclins may represent not-conserved pseudogenes. I am currently investigating whether the only conserved protein -coding cyclin is partially responsible for a residual cdk activity in interkinesis and whether SMG7 is involved in regulation of its activity

Identification of <i>Arabidopsis</i> Meiotic Cyclins Reveals Functional Diversification among Plant Cyclin Genes

<div><p>Meiosis is a modified cell division in which a single S-phase is followed by two rounds of chromosome segregation resulting in the production of haploid gametes. The meiotic mode of chromosome segregation requires extensive remodeling of the basic cell cycle machinery and employment of unique regulatory mechanisms. Cyclin-dependent kinases (CDKs) and cyclins represent an ancient molecular module that drives and regulates cell cycle progression. The cyclin gene family has undergone a massive expansion in angiosperm plants, but only a few cyclins were thoroughly characterized. In this study we performed a systematic immunolocalization screen to identify <i>Arabidopsis thaliana</i> A- and B-type cyclins expressed in meiosis. Many of these cyclins exhibit cell-type-specific expression in vegetative tissues and distinct subcellular localization. We found six A-type cyclins and a single B-type cyclin (CYCB3;1) to be expressed in male meiosis. Mutant analysis revealed that these cyclins contribute to distinct meiosis-related processes. While A2 cyclins are important for chromosome segregation, CYCB3;1 prevents ectopic cell wall formation. We further show that cyclin SDS does not contain a D-box and is constitutively expressed throughout meiosis. Analysis of plants carrying cyclin SDS with an introduced D-box motif determined that, in addition to its function in recombination, SDS acts together with CYCB3;1 in suppressing unscheduled cell wall synthesis. Our phenotypic and expression data provide extensive evidence that multiplication of cyclins is in plants accompanied by functional diversification.</p></div

Meiotic Progression in Arabidopsis Is Governed by Complex Regulatory Interactions between SMG7, TDM1, and the Meiosis I–Specific Cyclin TAM[W][OA]

Meiotic chromosome segregation requires extensive remodeling of cell cycle machinery. This work analyzes how TDM1, SMG7, and the cyclin TAM, which are essential for completion of meiosis, genetically interact to regulate meiotic progression in Arabidopsis pollen mother cells

Role of STN1 and DNA Polymerase α in Telomere Stability and Genome-Wide Replication in Arabidopsis

<div><p>The CST (Cdc13/CTC1-STN1-TEN1) complex was proposed to have evolved kingdom specific roles in telomere capping and replication. To shed light on its evolutionary conserved function, we examined the effect of STN1 dysfunction on telomere structure in plants. STN1 inactivation in <i>Arabidopsis</i> leads to a progressive loss of telomeric DNA and the onset of telomeric defects depends on the initial telomere size. While EXO1 aggravates defects associated with STN1 dysfunction, it does not contribute to the formation of long G-overhangs. Instead, these G-overhangs arise, at least partially, from telomerase-mediated telomere extension indicating a deficiency in C-strand fill-in synthesis. Analysis of hypomorphic DNA polymerase α mutants revealed that the impaired function of a general replication factor mimics the telomeric defects associated with CST dysfunction. Furthermore, we show that STN1-deficiency hinders re-replication of heterochromatic regions to a similar extent as polymerase α mutations. This comparative analysis of <i>stn1</i> and <i>pol α</i> mutants suggests that STN1 plays a genome-wide role in DNA replication and that chromosome-end deprotection in <i>stn1</i> mutants may represent a manifestation of aberrant replication through telomeres.</p></div