| 1. |
- Grimberg, Åsa, et al.
(författare)
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Transitions in wheat endosperm metabolism upon transcriptional induction of oil accumulation by oat endosperm WRINKLED1
- 2020
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Ingår i: BMC Plant Biology. - : Springer Science and Business Media LLC. - 1471-2229. ; 20
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Tidskriftsartikel (refereegranskat)abstract
- Background Cereal grains, including wheat (Triticum aestivum L.), are major sources of food and feed, with wheat being dominant in temperate zones. These end uses exploit the storage reserves in the starchy endosperm of the grain, with starch being the major storage component in most cereal species. However, oats (Avena sativa L.) differs in that the starchy endosperm stores significant amounts of oil. Understanding the control of carbon allocation between groups of storage compounds, such as starch and oil, is therefore important for understanding the composition and hence end use quality of cereals. WRINKLED1 is a transcription factor known to induce triacylglycerol (TAG; oil) accumulation in several plant storage tissues. Results An oat endosperm homolog of WRI1 (AsWRI1) expressed from the endosperm-specific HMW1Dx5 promoter resulted in drastic changes in carbon allocation in wheat grains, with reduced seed weight and a wrinkled seed phenotype. The starch content of mature grain endosperms of AsWRI1-wheat was reduced compared to controls (from 62 to 22% by dry weight (dw)), TAG was increased by up to nine-fold (from 0.7 to 6.4% oil by dw) and sucrose from 1.5 to 10% by dw. Expression of AsWRI1 in wheat grains also resulted in multiple layers of elongated peripheral aleurone cells. RNA-sequencing, lipid analyses, and pulse-chase experiments using C-14-sucrose indicated that futile cycling of fatty acids could be a limitation for oil accumulation. Conclusions Our data show that expression of oat endosperm WRI1 in the wheat endosperm results in changes in metabolism which could underpin the application of biotechnology to manipulate grain composition. In particular, the striking effect on starch synthesis in the wheat endosperm indicates that an important indirect role of WRI1 is to divert carbon allocation away from starch biosynthesis in plant storage tissues that accumulate oil.
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| 2. |
- Snell, Per, et al.
(författare)
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WRINKLED1 Is Subject to Evolutionary Conserved Negative Autoregulation
- 2019
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Ingår i: Frontiers in Plant Science. - : Frontiers Media SA. - 1664-462X. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- High accumulation of storage compounds such as oil and starch are economically important traits of most agricultural crops. The genetic network determining storage compounds composition in crops has been the target of many biotechnological endeavors. Especially WRINKLED1 (WRI1), a well-known key transcription factor involved in the allocation of carbon into oil, has attracted much interest. Here we investigate the presence of an autoregulatory system involving WRI1 through transient expression in Nicotiana benthamiana leaves. Different lengths of the Arabidopsis WRI1 promotor region were coupled to a GUS reporter gene and the activity was measured when combined with constitutive expression of different WRI1 homologs from Arabidopsis thaliana, oat (Avena sativa L.), yellow nutsedge (Cyperus esculentus L.), and potato (Solanum tuberosum L.). We could show that increasing levels of each WRI1 homolog reduced the transcriptional activity of the Arabidopsis WRI1 upstream region. Through structural analysis and domain swapping between oat and Arabidopsis WRI1, we were able to determine that the negative autoregulation was clearly dependent on the DNA-binding AP2-domains. A DNA/protein interaction assay showed that AtWRI1 is unable to bind to its corresponding upstream region indicating non-direct interaction in vivo. Taken together, our results demonstrate a negative feedback loop of WRI1 expression and that it is an indirect interaction most likely caused by downstream targets of WRI1. We also show that it is possible to release WRI1 expression from this autoregulation by creating semi-synthetic WRI1 homologs increasing the potential use of WRI1 in biotechnological applications.
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| 3. |
- Ahlgren, Serina, et al.
(författare)
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Miljöpåverkan av svensk nöt- och lammköttsproduktion
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Syftet med denna studie har varit att beräkna miljöpåverkan från olika svenska uppfödningsmodeller för nöt- och lammkött i produktionsområdena Götalands norra slättbygder, Götalands skogsbygder, Nedre Norrland samt del av Götalands mellanbygd (Gotland). Inom nötköttsproduktion har mjölkrastjur, mjölkrasstut, köttrastjur, köttrasstut och köttraskviga studerats. För lammkött har vårlamm, höstlamm och vinterlamm undersökts. Miljöpåverkanskategorier som ingått i studien är klimatpåverkan, markanvändning, kväveutsläpp samt påverkan på biologisk mångfald.
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| 4. |
- Carlsson, Anders, et al.
(författare)
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Replacing fossil oil with fresh oil - with what and for what?
- 2011
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Ingår i: European Journal of Lipid Science and Technology. - : Wiley. - 1438-7697 .- 1438-9312. ; 113, s. 812-831
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Forskningsöversikt (refereegranskat)abstract
- Industrial chemicals and materials are currently derived mainly from fossil-based raw materials, which are declining in availability, increasing in price and are a major source of undesirable greenhouse gas emissions. Plant oils have the potential to provide functionally equivalent, renewable and environmentally friendly replacements for these finite fossil-based raw materials, provided that their composition can be matched to end-use requirements, and that they can be produced on sufficient scale to meet current and growing industrial demands. Replacement of 40% of the fossil oil used in the chemical industry with renewable plant oils, whilst ensuring that growing demand for food oils is also met, will require a trebling of global plant oil production from current levels of around 139 MT to over 400 MT annually. Realisation of this potential will rely on application of plant biotechnology to (i) tailor plant oils to have high purity (preferably > 90%) of single desirable fatty acids, (ii) introduce unusual fatty acids that have specialty end-use functionalities and (iii) increase plant oil production capacity by increased oil content in current oil crops, and conversion of other high biomass crops into oil accumulating crops. This review outlines recent progress and future challenges in each of these areas.Practical applications: The research reviewed in this paper aims to develop metabolic engineering technologies to radically increase the yield and alter the fatty acid composition of plant oils and enable the development of new and more productive oil crops that can serve as renewable sources of industrial feedstocks currently provided by non-renewable and polluting fossil-based resources. As a result of recent and anticipated research developments we can expect to see significant enhancements in quality and productivity of oil crops over the coming decades. This should generate the technologies needed to support increasing plant oil production into the future, hopefully of sufficient magnitude to provide a major supply of renewable plant oils for the industrial economy without encroaching on the higher priority demand for food oils. Achievement of this goal will make a significant contribution to moving to a sustainable carbon-neutral industrial society with lower emissions of carbon dioxide to the atmosphere and reduced environmental impact as a result.
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| 5. |
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| 6. |
- Turesson, Helle, et al.
(författare)
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Characterization of oil and starch accumulation in tubers of Cyperus esculentus var. sativus (Cyperaceae): A novel model system to study oil reserves in nonseed tissues
- 2010
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Ingår i: American Journal of Botany. - : Wiley. - 0002-9122 .- 1537-2197. ; 97:11, s. 1884-1893
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Tidskriftsartikel (refereegranskat)abstract
- Premise of the study: Storage oil (triacylglycerol) accumulates in tissues such as the embryo and endosperm of seeds and the fruit mesocarp, but seldom in underground organs. As a rare exception, cultivated variants of yellow nutsedge (Cyperus esculentus) contain high amounts of both oil and starch in the mature tubers. Methods: Biochemical analyses and light and electron microscopy were used to study the accumulation patterns of storage nutrients in developing nutsedge tubers. Key results: During the initial phase of tuber development, the conducting rhizome tissue is transformed into a storage compartment, then massive storage reserves accumulate in the tuber. At the beginning of tuber development, a large sugar load coincided with the onset of starch accumulation. Oil accumulation started later, concomitant with a substantial drop in the sugar content. Initially, oil accumulated at a lower rate compared to starch, but the rate later increased; after 6 wk, oil made up 24% of tuber dry mass, while starch made up 32%. Protein concentration changed only a small amount throughout this development. Oil and starch accumulated in the same cells throughout the tubers in a sequential fashion during tuber development. Conclusions: The developmental pattern in the build up of storage nutrients in the tubers highlights nutsedge as a novel model plant, having potential to significantly widen our understanding on how synthesis of storage reserves, and in particular oils, is regulated and directed in nonseed tissues such as tubers and roots.
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| 7. |
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| 8. |
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| 9. |
- Carlsson, Lars, et al.
(författare)
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Adaptiv förvaltning
- 2010
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Ingår i: Vilt, människa, samhälle. - Stockholm : Liber. - 9789147094189 ; , s. 227-239
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 10. |
- Carlsson, Lars, et al.
(författare)
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Viltförvaltningens teoretiska grund
- 2010
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Ingår i: Vilt, människa, samhälle. - Stockholm : Liber. - 9789147094189 ; , s. 209-225
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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