SwePub - search: WFRF:(Sundström Jens)

Enumeration	Reference	Cover	Find
1.	Akhter, Shirin, et al. (author) Cone-setting in spruce is regulated by conserved elements of the age-dependent flowering pathway 2022 In: New Phytologist. - : Wiley. - 0028-646X .- 1469-8137. ; 236:5, s. 1951-1963 Journal article (peer-reviewed)abstract Reproductive phase change is well characterized in angiosperm model species, but less studied in gymnosperms. We utilize the early cone-setting acrocona mutant to study reproductive phase change in the conifer Picea abies (Norway spruce), a gymnosperm. The acrocona mutant frequently initiates cone-like structures, called transition shoots, in positions where wild-type P. abies always produces vegetative shoots. We collect acrocona and wild-type samples, and RNA-sequence their messenger RNA (mRNA) and microRNA (miRNA) fractions. We establish gene expression patterns and then use allele-specific transcript assembly to identify mutations in acrocona. We genotype a segregating population of inbred acrocona trees. A member of the SQUAMOSA BINDING PROTEIN-LIKE (SPL) gene family, PaSPL1, is active in reproductive meristems, whereas two putative negative regulators of PaSPL1, miRNA156 and the conifer specific miRNA529, are upregulated in vegetative and transition shoot meristems. We identify a mutation in a putative miRNA156/529 binding site of the acrocona PaSPL1 allele and show that the mutation renders the acrocona allele tolerant to these miRNAs. We show co-segregation between the early cone-setting phenotype and trees homozygous for the acrocona mutation. In conclusion, we demonstrate evolutionary conservation of the age-dependent flowering pathway and involvement of this pathway in regulating reproductive phase change in the conifer P. abies.
2.	Akhter, Shirin, et al. (author) Integrative Analysis of Three RNA Sequencing Methods Identifies Mutually Exclusive Exons of MADS-Box Isoforms During Early Bud Development in Picea abies 2018 In: Frontiers in Plant Science. - : Frontiers Media S.A.. - 1664-462X. ; 9 Journal article (peer-reviewed)abstract Recent efforts to sequence the genomes and transcriptomes of several gymnosperm species have revealed an increased complexity in certain gene families in gymnosperms as compared to angiosperms. One example of this is the gymnosperm sister Glade to angiosperm TM3-like MADS-box genes, which at least in the conifer lineage has expanded in number of genes. We have previously identified a member of this subclade, the conifer gene DEFICIENS AGAMOUS LIKE 19 (DAL19), as being specifically upregulated in cone-setting shoots. Here, we show through Sanger sequencing of mRNA-derived cDNA and mapping to assembled conifer genomic sequences that DAL19 produces six mature mRNA splice variants in Picea abies. These splice variants use alternate first and last exons, while their four central exons constitute a core region present in all six transcripts. Thus, they are likely to be transcript isoforms. Quantitative Real-Time PCR revealed that two mutually exclusive first DAL19 exons are differentially expressed across meristems that will form either male or female cones, or vegetative shoots. Furthermore, mRNA in situ hybridization revealed that two mutually exclusive last DAL19 exons were expressed in a cell-specific pattern within bud meristems. Based on these findings in DAL19, we developed a sensitive approach to transcript isoform assembly from short-read sequencing of mRNA. We applied this method to 42 putative MADS-box core regions in P abies, from which we assembled 1084 putative transcripts. We manually curated these transcripts to arrive at 933 assembled transcript isoforms of 38 putative MADS-box genes. 152 of these isoforms, which we assign to 28 putative MADS-box genes, were differentially expressed across eight female, male, and vegetative buds. We further provide evidence of the expression of 16 out of the 38 putative MADS-box genes by mapping PacBio Iso-Seq circular consensus reads derived from pooled sample sequencing to assembled transcripts. In summary, our analyses reveal the use of mutually exclusive exons of MADS-box gene isoforms during early bud development in P. abies, and we find that the large number of identified MADS-box transcripts in P. abies results not only from expansion of the gene family through gene duplication events but also from the generation of numerous splice variants.
3.	Akhter, Shirin, et al. (author) Transcriptome studies of the early cone-setting acrocona mutant provide evidence for a functional conservation of the age-dependent flowering pathway between angiosperms and gymnosperms. Other publication (other academic/artistic)abstract All seed plants go through a juvenile period before they initiate seed- and pollen-bearing organs and reproduce. Reproductive phase-change is well characterized in angiosperm model species, but much less well described in gymnosperms. Here, we utilize the early cone-setting acrocona mutant to study reproductive phase change in the conifer Picea abies; a representative of the gymnosperm lineage. The acrocona mutant frequently initiates cone-like structures, called transition shoots, in positions where wild-type P. abies always produces vegetative shoots. By sequence analysis of mRNA and microRNA transcripts, we demonstrate that orthologous components of the Age-dependent flowering pathway are active at the time of cone initiation. We show that a member of the SQUAMOSA BINDING PROTEIN-LIKE (SPL) gene family, PaSPL7, is active in reproductive meristems, whereas a putative negative regulator of PaSPL7, microRNA156 is upregulated in vegetative meristem. By allele-specific assembly, we also identify a short nucleotide polymorphism (SNP) in the miRNA156 binding of PaSPL7. By genotyping a segregating population of inbred acrocona trees, we show a clear co-segregation between the early cone-setting phenotype and trees homozygous for the SNP. Hence, the data presented demonstrate evolutionary conservation of the age-dependent flowering pathway and involvement of this pathway in regulating cone-setting in the conifer P. abies.
4.	Alderborn, Anders, et al. (author) Genetically modified plants for non-food or non-feed purposes : straightforward screening for their appearance in food and feed 2010 In: Food and Chemical Toxicology. - : Elsevier BV. - 0278-6915 .- 1873-6351. ; 48:2, s. 453-464 Journal article (peer-reviewed)abstract Genetically modified (GM) plants aimed at producing food/feed are part of regular agriculture in many areas of the World. Commodity plants have also found application as bioreactors, designated non-food/non-feed GM (NFGM) plants, thereby making raw material for further refinement to industrial, diagnostic or pharmaceutical preparations. Many among them may pose health challenge to consumers or livestock animals, if occurring in food/feed. NFGM plants are typically released into the environment, but are grown under special oversight and any among several containment practices, none of which provide full protection against accidental dispersal. Adventitious admixture with food or feed can occur either through distributional mismanagement or as a consequence of gene flow to plant relatives. To facilitate NFGM surveillance we propose a new mandatory tagging of essentially all such plants, prior to cultivation or marketing in the European Union. The suggested tag--Plant-Made Industrial or Pharmaceutical Products Tag (PMIP-T)--is envisaged to occur as a transgenic silent DNA identifier in host plants and designed to enable technically simple identification and characterisation of any NFGM. Implementation of PMIP-T would permit inexpensive, reliable and high-throughput screening for NFGM specifically. The paper outlines key NFGM prospects and challenges as well as the PMIP-T concept.
5.	Alexandersson, Erik, et al. (author) Tro får inte ersätta vetenskap 2014 In: Svenska dagbladet. - 1101-2412. Journal article (pop. science, debate, etc.)
6.	Almquist, Charlotta, et al. (author) Disease risk assessment of sugar beet root rot using quantitative real-time PCR analysis of Aphanomyces cochlioides in naturally infested soil samples 2016 In: European Journal of Plant Pathology. - : Springer Science and Business Media LLC. - 0929-1873 .- 1573-8469. ; 145, s. 731-742 Journal article (peer-reviewed)abstract Sugar beet root rot, caused by the oomycete Aphanomyces cochlioides, is a serious and economically important disease of sugar beets world-wide. Today, disease risk assessment consists of a time-consuming greenhouse bioassay using bait plants. In the present study, a real-time quantitative PCR (qPCR) assay for determination of A. cochlioides DNA in field-infested soil samples was developed and validated using the standard bioassay. The qPCR assay proved to be species-specific and was optimized to give high amplification efficiency suitable for target copy quantification. A high correlation (R-2 > 0.98, p < 0.001) with pathogen inoculum density was shown, demonstrating the suitability for monitoring soil samples. The limit of detection (LOD) was evaluated in several different soil types and varied between 1 and 50 oospores/g soil, depending on clay content. Soils with a high LOD were characterised as having a low clay content and high content of sand. Varying levels of the A. cochlioides target sequence were detected in 20 of the 61 naturally infested soil samples. Discrepancies between the bioassay and the qPCR assay were found in soils from low- and medium-risk fields. However, the qPCR diagnostic assay provides a potentially valuable new tool in disease risk assessment, enabling sugar beet growers to identify high-risk fields.
7.	Biasin, Elisa, et al. (author) Femtosecond X-Ray Scattering Study of Ultrafast Photoinduced Structural Dynamics in Solvated[Co(terpy)2]2$ 2016 In: Physical Review Letters. - : American Physical Society (APS). - 1079-7114 .- 0031-9007. ; 117:1 Journal article (peer-reviewed)abstract We study the structural dynamics of photoexcited [Co(terpy)2]2+ in an aqueous solution with ultrafast x-ray diffuse scattering experiments conducted at the Linac Coherent Light Source. Through direct comparisons with density functional theory calculations, our analysis shows that the photoexcitation event leads to elongation of the Co-N bonds, followed by coherent Co-N bond length oscillations arising from the impulsive excitation of a vibrational mode dominated by the symmetrical stretch of all six Co-N bonds. This mode has a period of 0.33 ps and decays on a subpicosecond time scale. We find that the equilibrium bond-elongated structure of the high spin state is established on a single-picosecond time scale and that this state has a lifetime of ∼7 ps.
8.	Canton, Sophie, et al. (author) Toward Highlighting the Ultrafast Electron Transfer Dynamics at the Optically Dark Sites of Photocatalysts 2013 In: The Journal of Physical Chemistry Letters. - : American Chemical Society (ACS). - 1948-7185. ; 4:11, s. 1972-1976 Journal article (peer-reviewed)abstract Building a detailed understanding of the structure function relationship is a crucial step in the optimization of molecular photocatalysts employed in water splitting schemes. The optically dark nature of their active sites usually prevents a complete mapping of the photoinduced dynamics. In this work, transient X-ray absorption spectroscopy highlights the electronic and geometric changes that affect such a center in a bimetallic model complex. Upon selective excitation of the ruthenium chromophore, the cobalt moiety is reduced through intramolecular electron transfer and undergoes a spin flip accompanied by an average bond elongation of 0.20 +/- 0.03 angstrom. The analysis is supported by simulations based on density functional theory structures (B3LYP*/TZVP) and FEFF 9.0 multiple scattering calculations. More generally, these results exemplify the large potential of the technique for tracking elusive intermediates that impart unique functionalities in photochemical devices.
9.	Canton, Sophie, et al. (author) Visualizing the non-equilibrium dynamics of photoinduced intramolecular electron transfer with femtosecond X-ray pulses. 2015 In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 6 Journal article (peer-reviewed)abstract Ultrafast photoinduced electron transfer preceding energy equilibration still poses many experimental and conceptual challenges to the optimization of photoconversion since an atomic-scale description has so far been beyond reach. Here we combine femtosecond transient optical absorption spectroscopy with ultrafast X-ray emission spectroscopy and diffuse X-ray scattering at the SACLA facility to track the non-equilibrated electronic and structural dynamics within a bimetallic donor-acceptor complex that contains an optically dark centre. Exploiting the 100-fold increase in temporal resolution as compared with storage ring facilities, these measurements constitute the first X-ray-based visualization of a non-equilibrated intramolecular electron transfer process over large interatomic distances. Experimental and theoretical results establish that mediation through electronically excited molecular states is a key mechanistic feature. The present study demonstrates the extensive potential of femtosecond X-ray techniques as diagnostics of non-adiabatic electron transfer processes in synthetic and biological systems, and some directions for future studies, are outlined.
10.	Carlsbecker, Annelie, et al. (author) Evolutionary diversification of the MADS-box gene family; an analysis of nine novel genes from the conifer Norway spruce Other publication (other academic/artistic)
11.	Carlsbecker, Annelie, et al. (author) Molecular control of normal and acrocona mutant seed cone development in Norway spruce (Picea abies) and the evolution of conifer ovule-bearing organs 2013 In: New Phytologist. - : Wiley. - 0028-646X .- 1469-8137. ; 200:1, s. 261-275 Journal article (peer-reviewed)abstract Reproductive organs in seed plants are morphologically divergent and their evolutionary history is often unclear. The mechanisms controlling their development have been extensively studied in angiosperms but are poorly understood in conifers and other gymnosperms. Here, we address the molecular control of seed cone development in Norway spruce, Picea abies. We present expression analyses of five novel MADS-box genes in comparison with previously identified MADS and LEAFY genes at distinct developmental stages. In addition, we have characterized the homeotic transformation from vegetative shoot to female cone and associated changes in regulatory gene expression patterns occurring in the acrocona mutant. The analyses identified genes active at the onset of ovuliferous and ovule development and identified expression patterns marking distinct domains of the ovuliferous scale. The reproductive transformation in acrocona involves the activation of all tested genes normally active in early cone development, except for an AGAMOUS-LIKE6/SEPALLATA (AGL6/SEP) homologue. This absence may be functionally associated with the nondeterminate development of the acrocona ovule-bearing scales. Our morphological and gene expression analyses give support to the hypothesis that the modern cone is a complex structure, and the ovuliferous scale the result of reductions and compactions of an ovule-bearing axillary short shoot in cones of Paleozoic conifers.
12.	Carlsbecker, Annelie, et al. (author) The DAL10 gene from Norway spruce (Picea abies) belongs to a potentially gymnosperm-specific subclass of MADS-box genes and is specifically active in seed cones and pollen cones. 2003 In: Evolution & Development. - : Blackwell publishing, INC. ; 5:6, s. 551-561 Journal article (peer-reviewed)
13.	Carlsbecker, Annelie, et al. (author) The DAL10 gene from Norway spruce Picea abies belongs to a potentially gymnosperm-specific subgroup of MADS-box genes and is specifically active in seed- and pollen cones Other publication (other academic/artistic)
14.	Carlsson, Jenny, et al. (author) Microarray analysis reveals altered expression of a large number of nuclear genes in developing cytoplasmic male sterile Brassica napus flowers 2007 In: The Plant Journal. - 0960-7412 .- 1365-313X. ; 49:3, s. 452-462 Journal article (peer-reviewed)abstract To gain new insights into the mechanism underlying cytoplasmic male sterility (CMS), we compared the nuclear gene expression profiles of flowers of a Brassica napus CMS line with that of the fertile B. napus maintainer line using Arabidopsis thaliana flower-specific cDNA microarrays. The CMS line used has a B. napus nuclear genome, but has a rearranged mitochondrial (mt) genome consisting of both B. napus and A. thaliana DNA. Gene expression profiling revealed that a large number of genes differed in expression between the two lines. For example, nuclear genes coding for proteins that are involved in protein import into organelles, genes expressed in stamens and pollen, as well as genes implicated in either cell-wall remodeling or architecture, were repressed in the CMS line compared with B. napus. These results show that the mt genome of the CMS line strongly influences nuclear gene expression, and thus reveal the importance of retrograde signalling between the mitochondria and the nucleus. Furthermore, flowers of the CMS line are characterized by a replacement of stamens with carpelloid organs, and thus partially resemble the APETALA3 (AP3) and PISTILLATA (PI) mutants. In accordance with this phenotype, AP3 expression was downregulated in the stamens, shortly before these organs developed carpelloid characteristics, even though it was initiated correctly. Repression of PI succeeded that of AP3 and might be a consequence of a loss of AP3 activity. These results suggest that AP3 expression in stamens depends on proper mt function and a correct nuclear-mt interaction, and that mt alterations cause the male sterility phenotype of the CMS line.
15.	Chábera, Pavel, et al. (author) A low-spin Fe(iii) complex with 100-ps ligand-to-metal charge transfer photoluminescence 2017 In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 543:7647, s. 695-699 Journal article (peer-reviewed)abstract Transition-metal complexes are used as photosensitizers1, in light-emitting diodes, for biosensing and in photocatalysis2. A key feature in these applications is excitation from the ground state to a charge-transfer state3,4; the long charge-transfer-state lifetimes typical for complexes of ruthenium5 and other precious metals are often essential to ensure high performance. There is much interest in replacing these scarce elements with Earth-abundant metals, with iron6 and copper7 being particularly attractive owing to their low cost and non-toxicity. But despite the exploration of innovative molecular designs6,8,9,10, it remains a formidable scientific challenge11 to access Earth-abundant transition-metal complexes with long-lived charge-transfer excited states. No known iron complexes are considered12 photoluminescent at room temperature, and their rapid excited-state deactivation precludes their use as photosensitizers13,14,15. Here we present the iron complex [Fe(btz)3]3+ (where btz is 3,3′-dimethyl-1,1′-bis(p-tolyl)-4,4′-bis(1,2,3-triazol-5-ylidene)), and show that the superior σ-donor and π-acceptor electron properties of the ligand stabilize the excited state sufficiently to realize a long charge-transfer lifetime of 100 picoseconds (ps) and room-temperature photoluminescence. This species is a low-spin Fe(iii) d5 complex, and emission occurs from a long-lived doublet ligand-to-metal charge-transfer (2LMCT) state that is rarely seen for transition-metal complexes4,16,17. The absence of intersystem crossing, which often gives rise to large excited-state energy losses in transition-metal complexes, enables the observation of spin-allowed emission directly to the ground state and could be exploited as an increased driving force in photochemical reactions on surfaces. These findings suggest that appropriate design strategies can deliver new iron-based materials for use as light emitters and photosensitizers.
16.	Chábera, Pavel, et al. (author) Band-selective dynamics in charge-transfer excited iron carbene complexes 2019 In: Faraday Discussions. - : Royal Society of Chemistry (RSC). - 1359-6640 .- 1364-5498. ; 216:2019, s. 191-210 Journal article (peer-reviewed)abstract Ultrafast dynamics of photoinduced charge transfer processes in light-harvesting systems based on Earth-abundant transition metal complexes are of current interest for the development of molecular devices for solar energy conversion applications. A combination of ultrafast spectroscopy and first principles quantum chemical calculations of a recently synthesized iron carbene complex is used to elucidate the ultrafast excited state evolution processes in these systems with particular emphasis on investigating the underlying reasons why these complexes show promise in terms of significantly extended lifetimes of charge transfer excited states. Together, our results challenge the traditional excited state landscape for iron-based light harvesting transition metal complexes through radically different ground and excited state properties in alternative oxidation states. This includes intriguing indications of rich band-selective excited state dynamics on ultrafast timescales that are interpreted in terms of excitation energy dependence for excitations into a manifold of charge-transfer states. Some implications of the observed excited state properties and photoinduced dynamics for the utilization of iron carbene complexes for solar energy conversion applications are finally discussed.
17.	Chábera, Pavel, et al. (author) FeII Hexa N-Heterocyclic Carbene Complex with a 528 ps Metal-To-Ligand Charge-Transfer Excited-State Lifetime 2018 In: Journal of Physical Chemistry Letters. - : American Chemical Society (ACS). - 1948-7185. ; 9:3, s. 459-463 Journal article (peer-reviewed)abstract The iron carbene complex [FeII(btz)3](PF6)2 (where btz = 3,3′-dimethyl-1,1′-bis(p-Tolyl)-4,4′-bis(1,2,3-Triazol-5-ylidene)) has been synthesized, isolated, and characterized as a low-spin ferrous complex. It exhibits strong metal-To-ligand charge transfer (MLCT) absorption bands throughout the visible spectrum, and excitation of these bands gives rise to a 3MLCT state with a 528 ps excited-state lifetime in CH3CN solution that is more than one order of magnitude longer compared with the MLCT lifetime of any previously reported FeII complex. The low potential of the [Fe(btz)3]3+/[Fe(btz)3]2+ redox couple makes the 3MLCT state of [FeII(btz)3]2+ a potent photoreductant that can be generated by light absorption throughout the visible spectrum. Taken together with our recent results on the [FeIII(btz)3]3+ form of this complex, these results show that the FeII and FeIII oxidation states of the same Fe(btz)3 complex feature long-lived MLCT and LMCT states, respectively, demonstrating the versatility of iron N-heterocyclic carbene complexes as promising light-harvesters for a broad range of oxidizing and reducing conditions.
18.	Chábera, Pavel, et al. (author) Photofunctionality of iron(III) N-heterocyclic carbenes and related d5 transition metal complexes 2021 In: Coordination Chemistry Reviews. - : Elsevier BV. - 0010-8545. ; 426 Research review (peer-reviewed)abstract Despite a few reports of photoluminescent and strongly photo-oxidizing transition metal complexes with a d5 electronic configuration, the photophysics and photochemistry of this class of transition metal complexes have largely remained unexplored. Recent investigations of earth-abundant iron(III) N-heterocyclic carbene (NHC) complexes have demonstrated promising photophysical and photochemical properties associated with low-spin (doublet) ligand-to-metal charge transfer (2LMCT) excitations, including nanosecond photoluminescence (PL) and capabilities to drive both photo-oxidation and photo-reduction reactions. These encouraging results are at first sight surprising in light of the general scarcity of known photofunctional complexes of any transition metal complexes with a d5 electronic configuration, including 1st, 2nd and 3rd row transition metal complexes of Mn(II), Tc(II), Re(II), Fe(III), Ru(III) and Os(III). Here, we review the photophysical and photochemical properties of the new Fe(III) NHC complexes together with related d5 transition metal complexes as a basis for a broader understanding of the unorthodox photophysical and photochemical properties associated with this open-shell electronic configuration. This includes considerations of the role of charge and spin effects on the ground state electronic structure, as well as discussions of charge transfer (CT) and metal centered (MC) excited state properties. The special properties of 2LMCT excited states are emphasized as a key feature to understand the photophysics of many photofunctional d5 transition metal complexes. Further aspects of excited state dynamics with d5 light-harvesting complexes, including both intra- and inter-molecular charge transfer processes, are also discussed. Finally, some fundamental challenges and emerging opportunities for further development of photofunctional Fe(III) NHC and related LMCT/d5 complexes for light-harvesting, light-emitting, and photo(electro)chemical applications are outlined. This includes some general considerations of how the specific photochemical properties of the LMCT/d5 complexes provides an exciting opportunity to develop a unique niche within the diversity of photofunctional molecular systems alongside other types of organic and inorganic chromophores commonly used in the field of molecular photochemistry.
19.	Dixelius, Christina, et al. (author) European agricultural policy goes down the tubers 2012 In: Nature Biotechnology. - : Springer Science and Business Media LLC. - 1087-0156 .- 1546-1696. ; 30, s. 492-493 Other publication (other academic/artistic)
20.	Eklund, Magnus, et al. (author) The Arabidopsis thaliana STYLISH1 Protein Acts as a Transcriptional Activator Regulating Auxin Biosynthesis 2010 In: The Plant Cell. - : Oxford University Press (OUP). - 1040-4651 .- 1532-298X. ; 22:2, s. 349-363 Journal article (peer-reviewed)abstract The establishment and maintenance of auxin maxima in vascular plants is regulated by auxin biosynthesis and polar intercellular auxin flow. The disruption of normal auxin biosynthesis in mouse-ear cress ( Arabidopsis thaliana) leads to severe abnormalities, suggesting that spatiotemporal regulation of auxin biosynthesis is fundamental for normal growth and development. We have shown previously that the induction of the SHORT-INTERNODES/STYLISH (SHI/STY) family member STY1 results in increased transcript levels of the YUCCA (YUC) family member YUC4 and also higher auxin levels and auxin biosynthesis rates in Arabidopsis seedlings. We have also shown previously that SHI/STY family members redundantly affect development of flowers and leaves. Here, we further examine the function of STY1 by analyzing its DNA and protein binding properties. Our results suggest that STY1, and most likely other SHI/STY members, are DNA binding transcriptional activators that target genes encoding proteins mediating auxin biosynthesis. This suggests that the SHI/STY family members are essential regulators of auxin-mediated leaf and flower development. Furthermore, the lack of a shoot apical meristem in seedlings carrying a fusion construct between STY1 and a repressor domain, SRDX, suggests that STY1, and other SHI/STY members, has a role in the formation and/or maintenance of the shoot apical meristem, possibly by regulating auxin levels in the embryo.
21.	Ericson, Fredric, et al. (author) Electronic structure and excited state properties of iron carbene photosensitizers - A combined X-ray absorption and quantum chemical investigation 2017 In: Chemical Physics Letters. - : Elsevier BV. - 0009-2614. ; 683, s. 559-566 Journal article (peer-reviewed)abstract The electronic structure and excited state properties of a series of iron carbene photosensitizers are elucidated through a combination of X-ray absorption measurements and density functional theory calculations. The X-ray absorption spectra are discussed with regard to the unusual bonding environment in these carbene complexes, highlighting the difference between ferrous and ferric carbene complexes. The valence electronic structure of the core excited FeIII-3d5 complex is predicted by calculating the properties of a CoIII-3d6 carbene complex using the Z+1 approximation. Insight is gained into the potential of sigma-donating ligands as strategy to tune properties for light harvesting applications.
22.	Eriksson, Dennis, et al. (author) A mistake about "GMO(s)", HT crops and herbicides 2016 In: Science. - 0036-8075 .- 1095-9203. ; 354, s. Online- Other publication (other academic/artistic)
23.	Fagerström, Torbjörn, et al. (author) Plant Biotechnology For a Bio-Based Economy 2014 Reports (other academic/artistic)
24.	Fagerström, Torbjörn, et al. (author) Stop worrying; start growing : Risk research on GM crops is a dead parrot: it is time to start reaping the benefits of GM 2012 In: EMBO Reports. - : EMBO. - 1469-221X .- 1469-3178. ; 13, s. 493-497 Other publication (other academic/artistic)
25.	Fullagar, Wilfred, et al. (author) A broadband laser plasma X-ray source for application in ultrafast chemical structure dynamics 2007 In: Review of Scientific Instruments. - : AIP Publishing. - 1089-7623 .- 0034-6748. ; 78:11, s. 1-115105 Journal article (peer-reviewed)abstract A plasma source free from characteristic emission lines is described, based on laser irradiation of a water jet in a helium atmosphere. Various key aspects of the laser interaction are presented along with practical characterization of the observed isotropic ~4–10 keV x-ray emissions, measurements of which indicate subpicosecond duration. Observations are consistent with a vacuum heating plasma mechanism at the helium-water interface and indicate strong potential for in-house ultrafast chemical structure dynamics application when coupled to contemporary detector developments.
26.	Fullagar, Wilfred K., et al. (author) Beating Darwin-Bragg losses in lab-based ultrafast X-ray experiments 2017 In: Structural Dynamics. - : AIP Publishing. - 2329-7778. ; 4:4 Journal article (peer-reviewed)abstract The use of low temperature thermal detectors for avoiding Darwin-Bragg losses in lab-based ultrafast experiments has begun. An outline of the background of this new development is offered, showing the relevant history and initiative taken by this work.
27.	Fullagar, Wilfred, et al. (author) Lab-based Ultrafast Molecular Structure. 2010 In: AIP Conference Proceedings. - : AIP. - 1551-7616 .- 0094-243X. ; 1234, s. 919-922 Conference paper (peer-reviewed)abstract The proliferation of various laser-driven approaches to sub-picosecond hard X-ray and short-wavelength radiation generation in the past few decades has opened many avenues for the laboratory-based development of traditionally facility-based short wavelength ultrafast molecular structure science. Together with the introduction of microcalorimeter detection schemes, this opens the floodgates to widespread, decentralized implementation of what were until recently specialist short wavelength techniques. A parallel situation exists for the contemporary adoption of sub-wavelength resolution optical microscopies. In what follows, a few ultrafast molecular structure developments and their rationale are briefly recounted.
28.	Fullagar, Wilfred, et al. (author) Radiations from a Water Jet Plasma Source 2007 In: ; , s. 7-7 Conference paper (other academic/artistic)
29.	Fullagar, Wilfred, et al. (author) The use and characterization of a backilluminated charge-coupled device in investigations of pulsed x-ray and radiation sources. 2008 In: Review of Scientific Instruments. - : AIP Publishing. - 1089-7623 .- 0034-6748. ; 79:10 Journal article (peer-reviewed)abstract Examinations of bremsstrahlung and energetic electron beams from a novel laser plasma source motivate and assist characterization of a backthinned, backilluminated direct detection x-ray charge-coupled device (CCD), a topology that is uncommon in hard x-ray work. Behavior toward pseudomonochromatic ((55)Fe) and multichromatic ((241)Am) sources is briefly reviewed under optimized noise conditions. Results collectively establish the previously unknown functional depth structure. Several modes of usage are illustrated in approximately 4-20 keV x-ray laser plasma source investigations, where the significance of the characterization is briefly discussed. The spectral redistribution associated with this CCD topology is unfavorable, yet appropriate analysis ensures that sufficient spectral information remains for quantitative determination of broadband x-ray flux and spectra in essentially single laser shot measurements. The energy dependence of nascent electron cloud radii in silicon is determined using broadband x-rays from the laser plasma source, turning the narrow depletion depth to advantage. Finally, the characterization is used to quantify recent x-ray spectral explorations of the water jet laser plasma source operating under aspirator vacuum. These results will have key value for establishment of laboratory based ultrafast extended x-ray absorption fine structure experiments using microbolometric detectors.
30.	Gawelda, Wojciech, et al. (author) Observing Solvation Dynamics with Simultaneous Femtosecond X-ray Emission Spectroscopy and X-ray Scattering 2016 In: The Journal of Physical Chemistry Part B. - : American Chemical Society (ACS). - 1520-5207 .- 1520-6106. ; 120:6, s. 1158-1168 Journal article (peer-reviewed)
31.	Giacomello, Stefania, et al. (author) Spatially resolved transcriptome profiling in model plant species 2017 In: Nature Plants. - : Springer Science and Business Media LLC. - 2055-026X .- 2055-0278. ; 3:6 Journal article (peer-reviewed)abstract Understanding complex biological systems requires functional characterization of specialized tissue domains. However, existing strategies for generating and analysing high-throughput spatial expression profiles were developed for a limited range of organisms, primarily mammals. Here we present the first available approach to generate and study highresolution, spatially resolved functional profiles in a broad range of model plant systems. Our process includes highthroughput spatial transcriptome profiling followed by spatial gene and pathway analyses. We first demonstrate the feasibility of the technique by generating spatial transcriptome profiles from model angiosperms and gymnosperms microsections. In Arabidopsis thaliana we use the spatial data to identify differences in expression levels of 141 genes and 189 pathways in eight inflorescence tissue domains. Our combined approach of spatial transcriptomics and functional profiling offers a powerful new strategy that can be applied to a broad range of plant species, and is an approach that will be pivotal to answering fundamental questions in developmental and evolutionary biology.
32.	Guerriera, Gea, et al. (author) The RY/Sph element mediates transcriptional repression of MAT genes from late maturation to early seedling growth 2009 In: New Phytologist. - : Wiley. - 0028-646X .- 1469-8137. ; 184:3, s. 552-565 Journal article (peer-reviewed)abstract P>In orthodox seeds, the transcriptional activator ABI3 regulates two major stages in embryo maturation: a mid-maturation (MAT) stage leading to accumulation of storage compounds, and a late maturation (LEA) stage leading to quiescence and desiccation tolerance. Our aim was to elucidate mechanisms for transcriptional shutdown of MAT genes during late maturation, to better understand phase transition between MAT and LEA stages. Using transgenic and transient approaches in Nicotiana, we examined activities of two ABI3-dependent reporter genes driven by multimeric RY and abscisic acid response elements (ABREs) from a Brassica napus napin gene, termed RY and ABRE, where the RY reporter requires ABI3 DNA binding. Expression of RY peaks during mid-maturation and drops during late maturation, mimicking the MAT gene program, and in Arabidopsis thaliana RY elements are over-represented in MAT, but not in LEA, genes. The ABI3 transactivation of RY is inhibited by staurosporine, by a PP2C phosphatase, and by a repressor of maturation genes, VAL1/HSI2. The RY element mediates repression of MAT genes, and we propose that transcriptional shutdown of the MAT program during late maturation involves inhibition of ABI3 DNA binding by dephosphorylation. Later, during seedling growth, VAL1/HSI2 family repressors silence MAT genes by binding RY elements.
33.	Guerriero, Gea, et al. (author) The RY/Sph element mediates transcriptional repression of maturation genes from late maturation to early seedling growth 2009 In: New Phytologist. - : Wiley. - 0028-646X .- 1469-8137. ; 184:3, s. 552-565 Journal article (peer-reviewed)abstract P>In orthodox seeds, the transcriptional activator ABI3 regulates two major stages in embryo maturation: a mid-maturation (MAT) stage leading to accumulation of storage compounds, and a late maturation (LEA) stage leading to quiescence and desiccation tolerance. Our aim was to elucidate mechanisms for transcriptional shutdown of MAT genes during late maturation, to better understand phase transition between MAT and LEA stages. Using transgenic and transient approaches in Nicotiana, we examined activities of two ABI3-dependent reporter genes driven by multimeric RY and abscisic acid response elements (ABREs) from a Brassica napus napin gene, termed RY and ABRE, where the RY reporter requires ABI3 DNA binding. Expression of RY peaks during mid-maturation and drops during late maturation, mimicking the MAT gene program, and in Arabidopsis thaliana RY elements are over-represented in MAT, but not in LEA, genes. The ABI3 transactivation of RY is inhibited by staurosporine, by a PP2C phosphatase, and by a repressor of maturation genes, VAL1/HSI2. The RY element mediates repression of MAT genes, and we propose that transcriptional shutdown of the MAT program during late maturation involves inhibition of ABI3 DNA binding by dephosphorylation. Later, during seedling growth, VAL1/HSI2 family repressors silence MAT genes by binding RY elements. New Phytologist (2009)doi: 10.1111/j.1469-8137.2009.02977.x.
34.	Hammarström, Leif, et al. (author) Time-Resolved Laser Spectroscopy in Molecular Devices for Solar Energy Conversion 2017 In: Molecular Devices for Solar Energy Conversion and Storage. - Singapore : Springer Singapore. - 2196-6990 .- 2196-6982. - 9789811059230 - 9789811059247 ; , s. 385-432 Book chapter (other academic/artistic)abstract A complete characterization of solar energy conversion devices and the processes underlying their function is a challenge, and require a multitude of different experimental methods. This chapter discusses investigations of molecular solar cells and solar fuels devices by time-resolved laser spectroscopic methods. These methods have established important concepts we now use for understanding the function of devices for solar energy conversion into primary products. We give examples of scientific insight provided by ultrafast methods using detection in the regions from X-ray to THz radiation, and particularly highlight the case where the use of different methods has provided complementary information. Charge collection and solar fuel catalysis on the other hand occur on longer time scales, which opens for the use of time-resolved magnetic resonance and microwave conductivity methods. We also point out that, with suitable precautions, time-resolved laser spectroscopy is able to give information relevant for in operando device conditions
35.	Harlang, Tobias, et al. (author) Iron sensitizer converts light to electrons with 92% yield. 2015 In: Nature Chemistry. - : Springer Science and Business Media LLC. - 1755-4330 .- 1755-4349. ; 7:11, s. 883-889 Journal article (peer-reviewed)abstract Solar energy conversion in photovoltaics or photocatalysis involves light harvesting, or sensitization, of a semiconductor or catalyst as a first step. Rare elements are frequently used for this purpose, but they are obviously not ideal for large-scale implementation. Great efforts have been made to replace the widely used ruthenium with more abundant analogues like iron, but without much success due to the very short-lived excited states of the resulting iron complexes. Here, we describe the development of an iron-nitrogen-heterocyclic-carbene sensitizer with an excited-state lifetime that is nearly a thousand-fold longer than that of traditional iron polypyridyl complexes. By the use of electron paramagnetic resonance, transient absorption spectroscopy, transient terahertz spectroscopy and quantum chemical calculations, we show that the iron complex generates photoelectrons in the conduction band of titanium dioxide with a quantum yield of 92% from the (3)MLCT (metal-to-ligand charge transfer) state. These results open up possibilities to develop solar energy-converting materials based on abundant elements.
36.	Harrison, Dick, et al. (author) Vikingatidens Europa 2018 In: Birkas skepp : vikingatid på Östersjön - vikingatid på Östersjön. - 0349-019X. - 9789173291316 ; 2018/2019, s. 10-49 Book chapter (peer-reviewed)
37.	Hillerdal, Gunnar, et al. (author) Malignant mesothelioma: prognosis not as bad as generally believed 2007 In: Journal of Thoracic Oncology. 12<SP>th</SP> World Conference on Lung Cancer, Seoul, Korea, September 2-6, 2007. 2(8) (Supplement 4):S599-S600, August 2007. ; , s. 599-600 Conference paper (other academic/artistic)
38.	Hillerdal, Gunnar, et al. (author) Treatment of malignant pleural mesothelioma with liposomized doxorubicine : prolonged time to progression and good survival. A Nordic study 2008 In: The Clinical Respiratory Journal. - 1752-6981 .- 1752-699X. ; 2:2, s. 80-85 Journal article (peer-reviewed)abstract Introduction: Malignant pleural mesothelioma (MPM) has a poor prognosis and there is limited effect of treatment. Lately, pemetrexed and cisplatin have been established as the standard treatment. Objectives: The present study was planned in 1998, when there was no standard treatment. Single-dose doxorubicine had, in small studies, accomplished remissions, and the Scandinavian Mesothelioma Groups therefore decided to test a liposomized form of this drug, which had shown limited toxicity but good efficacy in a few small studies. Methods: Fifty-four evaluable patients with histologically verified and inoperable MPM were treated with liposomized doxorubicine 40 mg/m2, every 4 weeks for six cycles. Results: In all, 29 patients (54%) received at least six treatments. The quality of life remained good during the study. Hematologic toxicity was very low. Palmo–plantar erythema occurred in 11 patients (20%), thereof 7 grade II but none was severe and none was dose-limiting. There were four partial responses (7%). The median time to progression (TTP) was 5 months, the median survival was 12 months, and at 24 months, 22% were still alive. Conclusion: Liposomized doxorubicine has a low toxicity and is well tolerated; there were a remarkably long TTP and a good survival. Thus, despite the low response rate, liposomized doxorubicine remains an interesting drug for the treatment of malignant mesothelioma.
39.	Hu, Jia, et al. (author) A low-methane rice with high-yield potential realized via optimized carbon partitioning 2024 In: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 920 Journal article (peer-reviewed)abstract Global rice cultivation significantly contributes to anthropogenic methane emissions. The methane emissions are caused by methane-producing microorganisms (methanogenic archaea) that are favoured by the anoxic conditions of paddy soils and small carbon molecules released from rice roots. However, different rice cultivars are associated with differences in methane emission rates suggesting that there is a considerable natural variation in this trait. Starting from the hypothesis that sugar allocation within a plant is an important factor influencing both yields and methane emissions, the aim of this study was to produce high-yielding rice lines associated with low methane emissions. In this study, the offspring (here termed progeny lines) of crosses between a newly characterized low-methane rice variety, Heijing 5, and three high-yielding elite varieties, Xiushui, Huayu and Jiahua, were selected for combined low-methane and high-yield properties. Analyses of total organic carbon and carbohydrates showed that the progeny lines stored more carbon in above-ground tissues than the maternal elite varieties. Also, metabolomic analysis of rhizospheric soil surrounding the progeny lines showed reduced levels of glucose and other carbohydrates. The carbon allocation, from roots to shoots, was further supported by a transcriptome analysis using massively parallel sequencing of mRNAs that demonstrated elevated expression of the sugar transporters SUT-C and SWEET in the progeny lines as compared to the parental varieties. Furthermore, measurement of methane emissions from plants, grown in greenhouse as well as outdoor rice paddies, showed a reduction in methane emissions by approximately 70 % in the progeny lines compared to the maternal elite varieties. Taken together, we report here on three independent low -methane -emission rice lines with high yield potential. We also provide a first molecular characterisation of the progeny lines that can serve as a foundation for further studies of candidate genes involved in sugar allocation and reduced methane emissions from rice cultivation.
40.	Hu, Jia, et al. (author) Characterisation of a low methane emission rice cultivar suitable for cultivation in high latitude light and temperature conditions 2023 In: Environmental Science and Pollution Research. - 0944-1344 .- 1614-7499. ; 30, s. 92950-92962 Journal article (peer-reviewed)abstract Rice cultivation on paddy soil is commonly associated with emissions of methane, a greenhouse gas, but rice varieties may differ in their actual level of emissions. This study analysed methane emissions associated with 22 distinct rice genotypes, using gas chromatography, and identified the cultivar Heijing 5 from northern China as a potential low-methane rice variety. To confirm this and to examine whether Heijing 5 can perform similarly at higher latitudes, Heijing 5 was cultivated in field trials in China (lat. 32° N) and Sweden (lat. 59° N) where (i) methane emissions were measured, (ii) methanogen abundance in the rhizosphere was determined using quantitative PCR, and (iii) the concentrations of nutrients in water and of heavy metals in rice grain and paddy soil were analysed. The results demonstrated that the low-methane rice cultivar Heijing 5 can successfully complete an entire growth period at high-latitude locations such as central Sweden. Massively parallel sequencing of mRNAs identified candidate genes involved in day length and cold acclimatisation. Cultivation of Heijing 5 in central Sweden was also associated with relatively low heavy metal accumulation in rice grains and lowered nutrient losses to neighbouring water bodies.
41.	Ingvarsson, Jens, et al. (author) Rubella virus seropositivity after infection or vaccination as a risk factor for multiple sclerosis 2024 In: European Journal of Neurology. - : John Wiley & Sons. - 1351-5101 .- 1468-1331. Journal article (peer-reviewed)abstract Background: Multiple sclerosis (MS) is a demyelinating disease affecting millions of people worldwide. Hereditary susceptibility and environmental factors contribute to disease risk. Infection with Epstein–Barr virus (EBV) and human herpesvirus 6A (HHV-6A) have previously been associated with MS risk. Other neurotropic viruses, such as rubella virus (RV), are possible candidates in MS aetiopathogenesis, but previous results are limited and conflicting.Methods: In this nested case–control study of biobank samples in a Swedish cohort, we analysed the serological response towards RV before the clinical onset of MS with a bead-based multiplex assay in subjects vaccinated and unvaccinated towards RV. The association between RV seropositivity and MS risk was analysed with conditional logistic regression.Results: Seropositivity towards RV was associated with an increased risk of MS for unvaccinated subjects, even when adjusting for plausible confounders including EBV, HHV-6A, cytomegalovirus and vitamin D (adjusted odds ratio [AOR] = 4.0, 95% confidence interval [CI] 1.8–8.8). Cases also had stronger antibody reactivity towards rubella than controls, which was not seen for other neurotropic viruses such as herpes simplex or varicella zoster. Furthermore, we observed an association between RV seropositivity and MS in vaccinated subjects. However, this association was not significant when adjusting for the aforementioned confounders (AOR = 1.7, 95% CI 1.0–2.9).Conclusions: To our knowledge, these are the first reported associations between early RV seropositivity and later MS development. This suggests a broadening of the virus hypothesis in MS aetiology, where molecular mimicry between rubella epitopes and human central nervous system molecules could be an attractive possible mechanism.
42.	Johansson, Carolina, et al. (author) Mutagenesis and homology modelling of the Tn21 integron integrase IntI1 2009 In: Biochemistry. - : American Chemical Society (ACS). - 0006-2960 .- 1520-4995. ; 48:8, s. 1743-1753 Journal article (peer-reviewed)abstract Horizontal DNA transfer between bacteria is widespread and a major cause of antibiotic resistance. For logistic reasons, single or combined genes are shuttled between vectors such as plasmids and bacterial chromosomes. Special elements termed integrons operate in such shuttling and are therefore vital for horizontal gene transfer. Shorter elements carrying genes, cassettes, are integrated in the integrons, or excised from them, by virtue of a recombination site, attC, positioned in the 3' end of each unit. It is a remarkable and possibly restricting elementary feature of attC that it must be single-stranded while the partner target site, attI, may be double-stranded. The integron integrases belong to the tyrosine recombinase family, and this work reports mutations of the integrase IntI1 from transposon Tn21, chosen within a well-conserved region characteristic of the integron integrases. The mutated proteins were tested for binding to a bottom strand of an attC substrate, by using an electrophoresis mobility shift assay. To aid in interpreting the results, a homology model was constructed on the basis of the crystal structure of integron integrase VchIntIA from Vibrio cholerae bound to its cognate attC substrate VCRbs. The local stability and hydrogen bonding network of key domains of the modeled structure were further examined using molecular dynamics simulations. The homology model allowed us to interpret the roles of several amino acid residues, four of which were clearly binding assay responsive upon mutagenesis. Notably, we also observed features indicating that IntI1 may be more prone to base-specific contacts with VCRbs than VchIntIA.
43.	Karlgren, Anna, et al. (author) Evolution of the PEBP Gene Family in Plants : Functional Diversification in Seed Plant Evolution 2011 In: Plant Physiology. - : Oxford University Press (OUP). - 0032-0889 .- 1532-2548. ; 156:4, s. 1967-1977 Journal article (peer-reviewed)abstract The phosphatidyl ethanolamine-binding protein (PEBP) gene family is present in all eukaryote kingdoms, with three subfamilies identified in angiosperms (FLOWERING LOCUS T [FT], MOTHER OF FT AND TFL1 [MFT], and TERMINAL FLOWER1 [TFL1] like). In angiosperms, PEBP genes have been shown to function both as promoters and suppressors of flowering and to control plant architecture. In this study, we focus on previously uncharacterized PEBP genes from gymnosperms. Extensive database searches suggest that gymnosperms possess only two types of PEBP genes, MFT-like and a group that occupies an intermediate phylogenetic position between the FT-like and TFL1-like (FT/TFL1-like). Overexpression of Picea abies PEBP genes in Arabidopsis (Arabidopsis thaliana) suggests that the FT/TFL1-like genes (PaFTL1 and PaFTL2) code for proteins with a TFL1-like function. However, PaFTL1 and PaFTL2 also show highly divergent expression patterns. While the expression of PaFTL2 is correlated with annual growth rhythm and mainly confined to needles and vegetative and reproductive buds, the expression of PaFTL1 is largely restricted to microsporophylls of male cones. The P. abies MFT-like genes (PaMFT1 and PaMFT2) show a predominant expression during embryo development, a pattern that is also found for many MFT-like genes from angiosperms. P. abies PEBP gene expression is primarily detected in tissues undergoing physiological changes related to growth arrest and dormancy. A first duplication event resulting in two families of plant PEBP genes (MFT-like and FT/TFL1-like) seems to coincide with the evolution of seed plants, in which independent control of bud and seed dormancy was required, and the second duplication resulting in the FT-like and TFL1-like clades probably coincided with the evolution of angiosperms.
44.	Karlgren, Anna, et al. (author) Non-radioactive in situ hybridization protocol applicable for Norway spruce and a range of plant species. 2009 In: Journal of Visualized Experiments. - : MyJove Corporation. - 1940-087X. ; :26 Journal article (peer-reviewed)
45.	Karlsson, Milla, et al. (author) Möjliga tillämpningar av nya genomiska tekniker inom integrerat växtskydd 2023 Reports (other academic/artistic)abstract Det pågår en omställning av jord- och trädgårdsbruket, både med hänsyn till hållbar produktion och pågående klimatförändringar. Som en del av EUs arbete att utveckla lantbruket mot en mer hållbar produktion har kommissionen lagt fram ett förslag på minskning av växtskyddsmedel om minst 50 %, totalt sett inom EU, senast 2030. För Sveriges del innebär förslaget, enligt preliminära beräkningar, att vi behöver minska mängden växtskyddsmedel med 35-36 %. För att ersätta funktionen av denna mängd växtskyddsmedel behövs ett integrerat tillvägagångssätt som kräver tillgång till andra effektiva metoder för bekämpning av skadegörare på odlade växter.Under det senaste decenniet har nya genomiska tekniker inom växtförädlingen utvecklats, vilka möjliggör riktade förändringar i många grödors genom. Teknikerna innebär antingen att man introducerar enstaka förändringar i DNA-sekvensen (s.k. genomredigering), eller att man sätter in en längre DNA-sekvens från samma art eller en korsningsbar art i en gröda (s.k. cisgenes). Dessutom har kunskapen om växters försvarssystem framskridit avsevärt. Med den ökade kunskapen och de nya teknikerna ökar möjligheten att kombinera gener och öka variationen av de gener som gör grödorna resistenta mot olika växtsjukdomar. På så sätt kan förädlingen av sjukdomsresistenta sorter ske med betydligt bättre precision och på kortare tid än vad traditionella förädlingstekniker tillåter. Tidsaspekten kan ses som extra viktig i resistenssammanhang eftersom skadegörarpopulationerna ändras kontinuerligt. Potentialen att kombinera flera olika resistensmekanismer för att uppnå mer uthållig resistens samt möjligheten att lösa ett eller flera växtskyddsproblem i samma sort bör också noteras.Enligt nuvarande EU-lagstiftning regleras dock genomredigerade och cisgena grödor på samma sätt som traditionellt genetiskt modifierade organismer (GMO), en lagstiftning som i praktiken omöjliggör kommersiell odling inom EU. Detta trots att resultatet av de moderna teknikerna kan efterlikna vad som kan ske spontant i naturen (mutationer) eller via traditionella oreglerade förädlingsmetoder (t.ex. mutations-, eller korsningsförädling). I lagstiftningen tas det ej i beaktande att sjukdomsresistenta grödor kan bidra till en minskad användning av växtskyddsmedel.Idag är potatisodling ofta förknippad med en användning av stora mängder växtskyddsmedel mot potatisbladmögel. Samtidigt är det möjligt att göra potatissorterna helt resistenta mot potatisbladmögel med hjälp av cisgenes och ge dem en ökad motståndskraft med hjälp av genomredigering. Om det vore möjligt att odla potatis som förädlats med nya genomiska tekniker inom EU idag, visar denna rapport att det skulle vara möjligt att kraftigt minska användningen av växtskyddsmedel i potatisodlingen. Det skulle innebära en reducering av mängden växtskyddsmedel som används inom det svenska lantbruket och skulle även innebära besparingar runt 91 miljoner SEK per år för odlarna.Vete och annan spannmål är de grödor där flest totala hektardoser av fungicider appliceras, till en årlig kostnad av två miljarder SEK. För dessa grödor finns inget lika tydligt exempel på enskilda sjukdomar som så kraftigt kan minska fungicidanvändningen. Vi ser dock en tydlig framtida potential att minska antalet bekämpningar och därmed kostnaden för lantbruket med hjälp av nya genomiska tekniker inom sädesslagen.Möjligheten att öka växters egen resistens för att minska användningen av växtskyddsmedel finns redan idag även i flera andra grödor, och möjligheterna förväntas fortsatt växa i takt med att teknikutveckling och forskning fortgår. En förändrad lagstiftning runt nya genomiska tekniker skulle även öppna för applikationer inom områden där det idag inte finns någon effektiv metod att bekämpa växtskadegörare. Exempel på sådana skadegörare är många virussjukdomar och skador som orsakas av nematoder. Därför kan skördestabiliteten och konkurrenskraften förväntas öka i grödor där det idag finns skadegörare där effektiva bekämpningsmetoder saknas.Sammanfattningsvis ser vi nya genomiska tekniker för att förädla resistenta grödor som en viktig del i arbetet mot ett hållbart jordbruk och för att uppnå EU-kommissionens mål om att reducera användningen av växtskyddsmedel inom jord- och trädgårdsbruket.
46.	Kennedy, Amanda, et al. (author) Structural Characterization of Agonist Binding to Protease-Activated Receptor 2 through Mutagenesis and Computational Modeling 2018 In: ACS Pharmacology & Translational Science. - : American Chemical Society (ACS). - 2575-9108. ; 1:2, s. 119-133 Journal article (peer-reviewed)abstract Protease-activated receptor 2 (PAR2) is a G protein-coupled receptor that is activated by proteolytic cleavage of its N-terminus. The unmasked N-terminal peptide then binds to the transmembrane bundle, leading to activation of intracellular signaling pathways associated with inflammation and cancer. Recently determined crystal structures have revealed binding sites of PAR2 antagonists, but the binding mode of the peptide agonist remains unknown. In order to generate a model of PAR2 in complex with peptide SLIGKV, corresponding to the trypsin-exposed tethered ligand, the orthosteric binding site was probed by iterative combinations of receptor mutagenesis, agonist ligand modifications and data-driven structural modeling. Flexible-receptor docking identified a conserved binding mode for agonists related to the endogenous ligand that was consistent with the experimental data and allowed synthesis of a novel peptide (1-benzyl-1H[1,2,3]triazole-4-yl-LIGKV) with higher functional potency than SLIGKV. The final model may be used to understand the structural basis of PAR2 activation and in virtual screens to identify novel PAR2 agonist and competitive antagonists. The combined experimental and computational approach to characterize agonist binding to PAR2 can be extended to study the many other G protein-coupled receptors that recognize peptides or proteins.
47.	Kjær, Kasper Skov, et al. (author) Luminescence and reactivity of a charge-transfer excited iron complex with nanosecond lifetime 2019 In: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 363:6424, s. 249-253 Journal article (peer-reviewed)abstract Iron’s abundance and rich coordination chemistry are potentially appealing features for photochemical applications. However, the photoexcitable charge-transfer (CT) states of most Fe complexes are limited by picosecond or sub-picosecond deactivation through low-lying metal centered (MC) states, resulting in inefficient electron transfer reactivity and complete lack of photoluminescence. Here we show that octahedral coordination of Fe(III) by two mono-anionic facial tris-carbene ligands can suppress such deactivation dramatically. The resulting complex [Fe(phtmeimb)2]+, where phtmeimb is [phenyl(tris(3-methylimidazol-1-ylidene))borate]-, exhibits strong, visible, room temperature photoluminescence with a 2.0 ns lifetime and 2% quantum yield via spin-allowed transition from a ligand-to-metal charge-transfer (2 LMCT) state to the ground state (2 GS). Reductive and oxidative electron transfer reactions were observed for the2 LMCT state of [Fe(phtmeimb)2]+ in bimolecular quenching studies with methylviologen and diphenylamine.
48.	Kleberg, Johan Lundin, et al. (author) Delayed gaze shifts away from others' eyes in children and adolescents with social anxiety disorder 2021 In: Journal of Affective Disorders. - : Elsevier. - 0165-0327 .- 1573-2517. ; 278, s. 280-287 Journal article (peer-reviewed)abstract Background: Social anxiety disorder (SAD) is linked to atypical attention to other's eyes. Empirical literature about this phenomenon in childhood and adolescence is scarce. Previous studies in adults have suggested that SAD may be characterized by either rapid avoidance of eye contact, or by impaired shifting of attention away from eyes once eye contact has been established. SAD has also been linked to quick orienting towards eyes, indicating vigilant monitoring of perceived threat. Methods: In the largest eye-tracking study of youth with SAD to date, 10 to 17 year-olds with SAD (n = 88) and healthy controls (n = 62) were primed to look at either the eyes or the mouth of human faces. The latency and likelihood of a first gaze shift from, or to the eyes, was measured. Results: Individuals with SAD were slower to shift their gaze away from the eye region of faces than controls, but did not differ in orienting toward eyes. Limitations: Participants were assessed once after the onset of SAD symptoms, meaning that the longitudinal predictive value of delayed gaze shifts from others' eyes could not be examined. Conclusions: Youth with SAD may be impaired in shifting attention from other's eyes. This could contribute to the experience of eye contact as aversive, and may be a maintaining factor of childhood SAD.
49.	Kunnus, Kristjan, et al. (author) Vibrational wavepacket dynamics in Fe carbene photosensitizer determined with femtosecond X-ray emission and scattering 2020 In: Nature Communications. - : Springer Nature. - 2041-1723. ; 11:1 Journal article (peer-reviewed)abstract The non-equilibrium dynamics of electrons and nuclei govern the function of photoactive materials. Disentangling these dynamics remains a critical goal for understanding photoactive materials. Here we investigate the photoinduced dynamics of the [Fe(bmip)2]2+ photosensitizer, where bmip = 2,6-bis(3-methyl-imidazole-1-ylidine)-pyridine, with simultaneous femtosecond-resolution Fe Kα and Kβ X-ray emission spectroscopy (XES) and X-ray solution scattering (XSS). This measurement shows temporal oscillations in the XES and XSS difference signals with the same 278 fs period oscillation. These oscillations originate from an Fe-ligand stretching vibrational wavepacket on a triplet metal-centered (3MC) excited state surface. This 3MC state is populated with a 110 fs time constant by 40% of the excited molecules while the rest relax to a 3MLCT excited state. The sensitivity of the Kα XES to molecular structure results from a 0.7% average Fe-ligand bond length shift between the 1 s and 2p core-ionized states surfaces.
50.	Larsson, Emma, et al. (author) Expression of PaNAC01, a Picea abies CUP-SHAPED COTYLEDON orthologue, is regulated by polar auxin transport and associated with differentiation of the shoot apical meristem and formation of separated cotyledons 2012 In: Annals of Botany. - : Oxford University Press (OUP). - 0305-7364 .- 1095-8290. ; 110, s. 923-934 Journal article (peer-reviewed)abstract During embryo development in most gymnosperms, the establishment of the shoot apical meristem (SAM) occurs concomitantly with the formation of a crown of cotyledons surrounding the SAM. It has previously been shown that the differentiation of cotyledons in somatic embryos of Picea abies is dependent on polar auxin transport (PAT). In the angiosperm model plant, Arabidopsis thaliana, the establishment of cotyledonary boundaries and the embryonal SAM is dependent on PAT and the expression of the CUP-SHAPED COTYLEDON (CUC) genes, which belong to the large NAC gene family. The aim of this study was to characterize CUC-like genes in a gymnosperm, and to elucidate their expression during SAM and cotyledon differentiation, and in response to PAT.Sixteen Picea glauca NAC sequences were identified in GenBank and deployed to different clades within the NAC gene family using maximum parsimony analysis and Bayesian inference. Motifs conserved between angiosperms and gymnosperms were analysed using the motif discovery tool MEME. Expression profiles during embryo development were produced using quantitative real-time PCR. Protein conservation was analysed by introducing a P. abies CUC orthologue into the A. thaliana cuc1cuc2 double mutant.Two full-length CUC-like cDNAs denoted PaNAC01 and PaNAC02 were cloned from P. abies. PaNAC01, but not PaNAC02, harbours previously characterized functional motifs in CUC1 and CUC2. The expression profile of PaNAC01 showed that the gene is PAT regulated and associated with SAM differentiation and cotyledon formation. Furthermore, PaNAC01 could functionally substitute for CUC2 in the A. thaliana cuc1cuc2 double mutant.The results show that CUC-like genes with distinct signature motifs existed before the separation of angiosperms and gymnosperms approx. 300 million years ago, and suggest a conserved function between PaNAC01 and CUC1/CUC2.

Skapa referenser, mejla, bekava och länka

Permalink

Träfflista för sökning "WFRF:(Sundström Jens) "

Refine your search

Year