| 231. |
- Janson, Sven, et al.
(författare)
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Host specificity in the Richelia - diatom symbiosis revealed by hetR gene sequence analysis
- 1999
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Ingår i: Environmental Microbiology. - 1462-2912 .- 1462-2920. ; 1:5, s. 431-438
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Tidskriftsartikel (refereegranskat)abstract
- The filamentous heterocyst-forming cyanobacterium Richelia intracellularis forms associations with diatoms and is very abundant in tropical and subtropical seas. The genus Richelia contains only one species, R. intracellularis Schmidt, although it forms associations with several diatom genera and has considerable variation in size and morphology. The genetic diversity, and possible host specificity, within the genus Richelia is unknown. Using primers against hetR, a gene unique for filamentous cyanobacteria, specific polymerase chain reaction (PCR) products were obtained from natural populations of R. intracellularis filaments associated with three diatom genera. Phylogenetic analyses of these sequences showed that they were all in the same clade. This clade contained only the R. intracellularis sequences. The genetic affiliation of hetR sequences of R. intracellularis to those of other heterocystous cyanobacteria strongly suggests that it was not closely related to endosymbiotic Nostoc spp, hetR sequences. Sequences from R, intracellularis-Hemiaulus membranaceus sampled in the Atlantic and Pacific Oceans were almost identical, demonstrating that the genetic relatedness was not dependent on geographical location, All sequences displayed a deep divergence between symbionts from different genera and a high degree of host specificity.
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| 232. |
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| 233. |
- Ke, Wenfan, et al.
(författare)
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Genes in human obesity loci are causal obesity genes in C. elegans
- 2021
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Ingår i: PLOS Genetics. - : Public Library of Science (PLoS). - 1553-7390 .- 1553-7404. ; 17:9
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Tidskriftsartikel (refereegranskat)abstract
- Obesity and its associated metabolic syndrome are a leading cause of morbidity and mortality in the United States. Given the disease's heavy burden on patients and the healthcare system, there has been increased interest in identifying pharmacological targets for the treatment and prevention of obesity. Towards this end, genome-wide association studies (GWAS) have identified hundreds of human genetic variants associated with obesity. The next challenge is to experimentally define which of these variants are causally linked to obesity, and could therefore become targets for the treatment or prevention of obesity. Here we employ high-throughput in vivo RNAi screening to test for causality 293 C. elegans orthologs of human obesity-candidate genes reported in GWAS. We RNAi screened these 293 genes in C. elegans subject to two different feeding regimens: (1) regular diet, and (2) high-fructose diet, which we developed and present here as an invertebrate model of diet-induced obesity (DIO). We report 14 genes that promote obesity and 3 genes that prevent DIO when silenced in C. elegans. Further, we show that knock-down of the 3 DIO genes not only prevents excessive fat accumulation in primary and ectopic fat depots but also improves the health and extends the lifespan of C. elegans overconsuming fructose. Importantly, the direction of the association between expression variants in these loci and obesity in mice and humans matches the phenotypic outcome of the loss-of-function of the C. elegans ortholog genes, supporting the notion that some of these genes would be causally linked to obesity across phylogeny. Therefore, in addition to defining causality for several genes so far merely correlated with obesity, this study demonstrates the value of model systems compatible with in vivo high-throughput genetic screening to causally link GWAS gene candidates to human diseases. Author summary Human GWAS have identified hundreds of genetic variants associated with human obesity. The genes being regulated by these variants at the protein or expression level represent potential anti-obesity targets. However, for the vast majority of these genes, it is unclear whether they cause obesity or are coincidentally associated with the disease. Here we use a high-throughput genetic screening strategy to test in vivo in Caenorhabditis elegans the potential causal role of human-obesity GWAS hits. Further, we combined the results of the genetic screen with analyses of mouse and human GWAS databases. As a result, we present 17 genes that promote or prevent C. elegans obesity, and the early onset of organismal deterioration and death associated with obesity. Further, the sign of the correlation between the expression levels of the human genes and their associated clinical traits matches, for the most part, the phenotypic effects of knocking down these genes in C. elegans, suggesting conserved causality and pharmacological potential for these genes.
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| 234. |
- Kok, Marcel T. J., et al.
(författare)
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Biodiversity and ecosystem services require IPBES to take novel approach to scenarios
- 2017
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Ingår i: Sustainability Science. - : Springer Science and Business Media LLC. - 1862-4065 .- 1862-4057. ; 12:1, s. 177-181
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- What does the future hold for the world's ecosystems and benefits that people obtain from them? While the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) has identified the development of scenarios as a key to helping decision makers identify potential impacts of different policy options, it currently lacks a long-term scenario strategy. IPBES will decide how it will approach scenarios at its plenary meeting on 22-28 February 2016, in Kuala Lumpur. IPBES now needs to decide whether it should create new scenarios that better explore ecosystem services and biodiversity dynamics. For IPBES to capture the social-ecological dynamics of biodiversity and ecosystem services, it is essential to engage with the great diversity of local contexts, while also including the global tele-coupling among local places. We present and compare three alternative scenario strategies that IPBES could use and then suggest a bottom-up, cross-scale scenario strategy to improve the policy relevance of future IPBES assessments. We propose five concrete steps as part of an effective, long term scenario development process for IPBES in cooperation with the scientific community.
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| 235. |
- Küpper, Frithjof C., et al.
(författare)
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Commemorating Two Centuries of Iodine Research : An Interdisciplinary Overview of Current Research
- 2011
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Ingår i: Angewandte Chemie International Edition. - : Wiley. - 1433-7851 .- 1521-3773. ; 50:49, s. 11598-11620
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Forskningsöversikt (refereegranskat)abstract
- Iodine was discovered as a novel element in 1811 during the Napoleonic Wars. To celebrate the bicentennial anniversary of this event we reflect on the history and highlight the many facets of iodine research that have evolved since its discovery. Iodine has an impact on many aspects of life on Earth as well as on human civilization. It is accumulated in high concentrations by marine algae, which are the origin of strong iodine fluxes into the coastal atmosphere which influence climatic processes, and dissolved iodine is considered a biophilic element in marine sediments. Iodine is central to thyroid function in vertebrates, with paramount implications for human health. Iodine can exist in a wide range of oxidation states and it features a diverse supramolecular chemistry. Iodine is amenable to several analytical techniques, and iodine compounds have found widespread use in organic synthesis. Elemental iodine is produced on an industrial scale and has found a wide range of applications in innovative materials, including semiconductorsin particular, in solar cells.
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| 236. |
- Küpper, Frithjof C., et al.
(författare)
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Purple fumes : the importance of iodine
- 2013
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Ingår i: Science in School. - 1818-0353 .- 1818-0361. ; :27, s. 45-53
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 237. |
- Lade, Steven J., et al.
(författare)
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Human impacts on planetary boundaries amplified by Earth system interactions
- 2020
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Ingår i: Nature Sustainability. - : Springer Science and Business Media LLC. - 2398-9629. ; 3:2, s. 119-128
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Tidskriftsartikel (refereegranskat)abstract
- The planetary boundary framework presents a ‘planetary dashboard’ of humanity’s globally aggregated performance on a set of environmental issues that endanger the Earth system’s capacity to support humanity. While this framework has been highly influential, a critical shortcoming for its application in sustainability governance is that it currently fails to represent how impacts related to one of the planetary boundaries affect the status of other planetary boundaries. Here, we surveyed and provisionally quantified interactions between the Earth system processes represented by the planetary boundaries and investigated their consequences for sustainability governance. We identified a dense network of interactions between the planetary boundaries. The resulting cascades and feedbacks predominantly amplify human impacts on the Earth system and thereby shrink the safe operating space for future human impacts on the Earth system. Our results show that an integrated understanding of Earth system dynamics is critical to navigating towards a sustainable future.
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| 238. |
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| 239. |
- Linnarsson, D, et al.
(författare)
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Toxicity of lunar dust
- 2012
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Ingår i: PLANETARY AND SPACE SCIENCE. - : Elsevier BV. - 0032-0633. ; 74:1, s. 57-71
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 240. |
- Lipoglavsek, M, et al.
(författare)
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100Sn Core Excitations in 102In
- 2002
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Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 65:2
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Tidskriftsartikel (refereegranskat)abstract
- Nuclei in the vicinity of the doubly-magic Sn-100 nucleus have been studied, and an extended level scheme for In-102 has been established. The level structure comprises both the negative parity states involving the nuh(11/2) orbital, and levels due to the breakup of the doubly-magic Sn-100 core. Results of a large-scale shell model calculation, using realistic and empirical effective interactions with Sr-88 as a core, are in very good agreement with the experimental data.
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