GLORIA

GEOMAR Library Ocean Research Information Access

X

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • Proceedings of the National Academy of Sciences  (15)
  • Naturwissenschaft allgemein  (15)
Materialart
Verlag/Herausgeber
  • Proceedings of the National Academy of Sciences  (15)
Person/Organisation
Sprache
Erscheinungszeitraum
FID
Fachgebiete(RVK)
  • Naturwissenschaft allgemein  (15)
  • Biologie  (15)
RVK
  • 1
    Online-Ressource
    Online-Ressource
    Sunlight exposure exerts immunomodulatory effects to reduce multiple sclerosis severity
    Proceedings of the National Academy of Sciences ; 2021
    In:  Proceedings of the National Academy of Sciences Vol. 118, No. 1 ( 2021-01-05)
    Details
    In: Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 118, No. 1 ( 2021-01-05)
    Kurzfassung: Multiple sclerosis (MS) disease risk is associated with reduced sun-exposure. This study assessed the relationship between measures of sun exposure (vitamin D [vitD], latitude) and MS severity in the setting of two multicenter cohort studies ( n NationMS = 946, n BIONAT = 990). Additionally, effect-modification by medication and photosensitivity-associated MC1R variants was assessed. High serum vitD was associated with a reduced MS severity score (MSSS), reduced risk for relapses, and lower disability accumulation over time. Low latitude was associated with higher vitD, lower MSSS, fewer gadolinium-enhancing lesions, and lower disability accumulation. The association of latitude with disability was lacking in IFN-β–treated patients. In carriers of MC1R :rs1805008(T), who reported increased sensitivity toward sunlight, lower latitude was associated with higher MRI activity, whereas for noncarriers there was less MRI activity at lower latitudes. In a further exploratory approach, the effect of ultraviolet (UV)-phototherapy on the transcriptome of immune cells of MS patients was assessed using samples from an earlier study. Phototherapy induced a vitD and type I IFN signature that was most apparent in monocytes but that could also be detected in B and T cells. In summary, our study suggests beneficial effects of sun exposure on established MS, as demonstrated by a correlative network between the three factors: Latitude, vitD, and disease severity. However, sun exposure might be detrimental for photosensitive patients. Furthermore, a direct induction of type I IFNs through sun exposure could be another mechanism of UV-mediated immune-modulation in MS.
    Materialart: Online-Ressource
    ISSN: 0027-8424 , 1091-6490
    URL: Article
    DOI: 10.1073/pnas.2018457118
    RVK:
    TA 1000
    RVK:
    WA 15000
    Sprache: Englisch
    Verlag: Proceedings of the National Academy of Sciences
    Publikationsdatum: 2021
    ZDB Id: 209104-5
    ZDB Id: 1461794-8
    SSG: 11
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Online-Ressource
  • 2
    Online-Ressource
    Online-Ressource
    Electron–hole asymmetry of the topological surface states in strained HgTe
    Proceedings of the National Academy of Sciences ; 2017
    In:  Proceedings of the National Academy of Sciences Vol. 114, No. 13 ( 2017-03-28), p. 3381-3386
    Details
    In: Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 114, No. 13 ( 2017-03-28), p. 3381-3386
    Kurzfassung: Topological insulators are a new class of materials with an insulating bulk and topologically protected metallic surface states. Although it is widely assumed that these surface states display a Dirac-type dispersion that is symmetric above and below the Dirac point, this exact equivalence across the Fermi level has yet to be established experimentally. Here, we present a detailed transport study of the 3D topological insulator-strained HgTe that strongly challenges this prevailing viewpoint. First, we establish the existence of exclusively surface-dominated transport via the observation of an ambipolar surface quantum Hall effect and quantum oscillations in the Seebeck and Nernst effect. Second, we show that, whereas the thermopower is diffusion driven for surface electrons, both diffusion and phonon drag contributions are essential for the hole surface carriers. This distinct behavior in the thermoelectric response is explained by a strong deviation from the linear dispersion relation for the surface states, with a much flatter dispersion for holes compared with electrons. These findings show that the metallic surface states in topological insulators can exhibit both strong electron–hole asymmetry and a strong deviation from a linear dispersion but remain topologically protected.
    Materialart: Online-Ressource
    ISSN: 0027-8424 , 1091-6490
    URL: Article
    DOI: 10.1073/pnas.1611663114
    RVK:
    TA 1000
    RVK:
    WA 15000
    Sprache: Englisch
    Verlag: Proceedings of the National Academy of Sciences
    Publikationsdatum: 2017
    ZDB Id: 209104-5
    ZDB Id: 1461794-8
    SSG: 11
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Online-Ressource
  • 3
    Online-Ressource
    Online-Ressource
    Models of the complement C1 complex
    Proceedings of the National Academy of Sciences ; 2018
    In:  Proceedings of the National Academy of Sciences Vol. 115, No. 17 ( 2018-04-24)
    Details
    In: Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 115, No. 17 ( 2018-04-24)
    Materialart: Online-Ressource
    ISSN: 0027-8424 , 1091-6490
    URL: Article
    DOI: 10.1073/pnas.1803577115
    RVK:
    TA 1000
    RVK:
    WA 15000
    Sprache: Englisch
    Verlag: Proceedings of the National Academy of Sciences
    Publikationsdatum: 2018
    ZDB Id: 209104-5
    ZDB Id: 1461794-8
    SSG: 11
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Online-Ressource
  • 4
    Online-Ressource
    Online-Ressource
    Enhanced incorporation of subnanometer tags into cellular proteins for fluorescence nanoscopy via optimized genetic code expansion
    Proceedings of the National Academy of Sciences ; 2022
    In:  Proceedings of the National Academy of Sciences Vol. 119, No. 29 ( 2022-07-19)
    Details
    In: Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 119, No. 29 ( 2022-07-19)
    Kurzfassung: With few-nanometer resolution recently achieved by a new generation of fluorescence nanoscopes (MINFLUX and MINSTED), the size of the tags used to label proteins will increasingly limit the ability to dissect nanoscopic biological structures. Bioorthogonal (click) chemical groups are powerful tools for the specific detection of biomolecules. Through the introduction of an engineered aminoacyl–tRNA synthetase/tRNA pair (tRNA: transfer ribonucleic acid), genetic code expansion allows for the site-specific introduction of amino acids with “clickable” side chains into proteins of interest. Well-defined label positions and the subnanometer scale of the protein modification provide unique advantages over other labeling approaches for imaging at molecular-scale resolution. We report that, by pairing a new N-terminally optimized pyrrolysyl–tRNA synthetase (chPylRS 2020 ) with a previously engineered orthogonal tRNA, clickable amino acids are incorporated with improved efficiency into bacteria and into mammalian cells. The resulting enhanced genetic code expansion machinery was used to label β-actin in U2OS cell filopodia for MINFLUX imaging with minimal separation of fluorophores from the protein backbone. Selected data were found to be consistent with previously reported high-resolution information from cryoelectron tomography about the cross-sectional filament bundling architecture. Our study underscores the need for further improvements to the degree of labeling with minimal-offset methods in order to fully exploit molecular-scale optical three-dimensional resolution.
    Materialart: Online-Ressource
    ISSN: 0027-8424 , 1091-6490
    URL: Article
    DOI: 10.1073/pnas.2201861119
    RVK:
    TA 1000
    RVK:
    WA 15000
    Sprache: Englisch
    Verlag: Proceedings of the National Academy of Sciences
    Publikationsdatum: 2022
    ZDB Id: 209104-5
    ZDB Id: 1461794-8
    SSG: 11
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Online-Ressource
  • 5
    Online-Ressource
    Online-Ressource
    Dimensions of invasiveness: Links between local abundance, geographic range size, and habitat breadth in Europe’s alien and native floras
    Proceedings of the National Academy of Sciences ; 2021
    In:  Proceedings of the National Academy of Sciences Vol. 118, No. 22 ( 2021-06)
    Details
    In: Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 118, No. 22 ( 2021-06)
    Kurzfassung: Understanding drivers of success for alien species can inform on potential future invasions. Recent conceptual advances highlight that species may achieve invasiveness via performance along at least three distinct dimensions: 1) local abundance, 2) geographic range size, and 3) habitat breadth in naturalized distributions. Associations among these dimensions and the factors that determine success in each have yet to be assessed at large geographic scales. Here, we combine data from over one million vegetation plots covering the extent of Europe and its habitat diversity with databases on species’ distributions, traits, and historical origins to provide a comprehensive assessment of invasiveness dimensions for the European alien seed plant flora. Invasiveness dimensions are linked in alien distributions, leading to a continuum from overall poor invaders to super invaders—abundant, widespread aliens that invade diverse habitats. This pattern echoes relationships among analogous dimensions measured for native European species. Success along invasiveness dimensions was associated with details of alien species’ introduction histories: earlier introduction dates were positively associated with all three dimensions, and consistent with theory-based expectations, species originating from other continents, particularly acquisitive growth strategists, were among the most successful invaders in Europe. Despite general correlations among invasiveness dimensions, we identified habitats and traits associated with atypical patterns of success in only one or two dimensions—for example, the role of disturbed habitats in facilitating widespread specialists. We conclude that considering invasiveness within a multidimensional framework can provide insights into invasion processes while also informing general understanding of the dynamics of species distributions.
    Materialart: Online-Ressource
    ISSN: 0027-8424 , 1091-6490
    URL: Article
    DOI: 10.1073/pnas.2021173118
    RVK:
    TA 1000
    RVK:
    WA 15000
    Sprache: Englisch
    Verlag: Proceedings of the National Academy of Sciences
    Publikationsdatum: 2021
    ZDB Id: 209104-5
    ZDB Id: 1461794-8
    SSG: 11
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Online-Ressource
  • 6
    Online-Ressource
    Online-Ressource
    Colloidal quasicrystals with 12-fold and 18-fold diffraction symmetry
    Proceedings of the National Academy of Sciences ; 2011
    In:  Proceedings of the National Academy of Sciences Vol. 108, No. 5 ( 2011-02), p. 1810-1814
    Details
    In: Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 108, No. 5 ( 2011-02), p. 1810-1814
    Kurzfassung: Micelles are the simplest example of self-assembly found in nature. As many other colloids, they can self-assemble in aqueous solution to form ordered periodic structures. These structures so far all exhibited classical crystallographic symmetries. Here we report that micelles in solution can self-assemble into quasicrystalline phases. We observe phases with 12-fold and 18-fold diffraction symmetry. Colloidal water-based quasicrystals are physically and chemically very simple systems. Macroscopic monodomain samples of centimeter dimension can be easily prepared. Phase transitions between the fcc phase and the two quasicrystalline phases can be easily followed in situ by time-resolved diffraction experiments. The discovery of quasicrystalline colloidal solutions advances the theoretical understanding of quasicrystals considerably, as for these systems the stability of quasicrystalline states has been theoretically predicted for the concentration and temperature range, where they are experimentally observed. Also for the use of quasicrystals in advanced materials this discovery is of particular importance, as it opens the route to quasicrystalline photonic band gap materials via established water-based colloidal self-assembly techniques.
    Materialart: Online-Ressource
    ISSN: 0027-8424 , 1091-6490
    URL: Article
    DOI: 10.1073/pnas.1008695108
    RVK:
    TA 1000
    RVK:
    WA 15000
    Sprache: Englisch
    Verlag: Proceedings of the National Academy of Sciences
    Publikationsdatum: 2011
    ZDB Id: 209104-5
    ZDB Id: 1461794-8
    SSG: 11
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Online-Ressource
  • 7
    Online-Ressource
    Online-Ressource
    Structure and activation of C1, the complex initiating the classical pathway of the complement cascade
    Proceedings of the National Academy of Sciences ; 2017
    In:  Proceedings of the National Academy of Sciences Vol. 114, No. 5 ( 2017-01-31), p. 986-991
    Details
    In: Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 114, No. 5 ( 2017-01-31), p. 986-991
    Kurzfassung: The complement system is an important antimicrobial and inflammation-generating component of the innate immune system. The classical pathway of complement is activated upon binding of the 774-kDa C1 complex, consisting of the recognition molecule C1q and the tetrameric protease complex C1r 2 s 2 , to a variety of activators presenting specific molecular patterns such as IgG- and IgM-containing immune complexes. A canonical model entails a C1r 2 s 2 with its serine protease domains tightly packed together in the center of C1 and an intricate intramolecular reaction mechanism for activation of C1r and C1s, induced upon C1 binding to the activator. Here, we show that the serine protease domains of C1r and C1s are located at the periphery of the C1r 2 s 2 tetramer both when alone or within the nonactivated C1 complex. Our structural studies indicate that the C1 complex adopts a conformation incompatible with intramolecular activation of C1, suggesting instead that intermolecular proteolytic activation between neighboring C1 complexes bound to a complement activating surface occurs. Our results rationalize how a multitude of structurally unrelated molecular patterns can activate C1 and suggests a conserved mechanism for complement activation through the classical and the related lectin pathway.
    Materialart: Online-Ressource
    ISSN: 0027-8424 , 1091-6490
    URL: Article
    DOI: 10.1073/pnas.1616998114
    RVK:
    TA 1000
    RVK:
    WA 15000
    Sprache: Englisch
    Verlag: Proceedings of the National Academy of Sciences
    Publikationsdatum: 2017
    ZDB Id: 209104-5
    ZDB Id: 1461794-8
    SSG: 11
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Online-Ressource
  • 8
    Online-Ressource
    Online-Ressource
    Reply to Arlaud et al.: Structure of the C1 complex and the unbound C1r 2 s 2 tetramer
    Proceedings of the National Academy of Sciences ; 2017
    In:  Proceedings of the National Academy of Sciences Vol. 114, No. 29 ( 2017-07-18)
    Details
    In: Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 114, No. 29 ( 2017-07-18)
    Materialart: Online-Ressource
    ISSN: 0027-8424 , 1091-6490
    URL: Article
    DOI: 10.1073/pnas.1704353114
    RVK:
    TA 1000
    RVK:
    WA 15000
    Sprache: Englisch
    Verlag: Proceedings of the National Academy of Sciences
    Publikationsdatum: 2017
    ZDB Id: 209104-5
    ZDB Id: 1461794-8
    SSG: 11
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Online-Ressource
  • 9
    Online-Ressource
    Online-Ressource
    CX 3 CR1 + CD8α + dendritic cells are a steady-state population related to plasmacytoid dendritic cells
    Proceedings of the National Academy of Sciences ; 2010
    In:  Proceedings of the National Academy of Sciences Vol. 107, No. 33 ( 2010-08-17), p. 14745-14750
    Details
    In: Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 107, No. 33 ( 2010-08-17), p. 14745-14750
    Kurzfassung: Lymphoid organs are characterized by a complex network of phenotypically distinct dendritic cells (DC) with potentially unique roles in pathogen recognition and immunostimulation. Classical DC (cDC) include two major subsets distinguished in the mouse by the expression of CD8α. Here we describe a subset of CD8α + DC in lymphoid organs of naïve mice characterized by expression of the CX 3 CR1 chemokine receptor. CX 3 CR1 + CD8α + DC lack hallmarks of classical CD8α + DC, including IL-12 secretion, the capacity to cross-present antigen, and their developmental dependence on the transcriptional factor BatF3. Gene-expression profiling showed that CX 3 CR1 + CD8α + DC resemble CD8α − cDC. The microarray analysis further revealed a unique plasmacytoid DC (PDC) gene signature of CX 3 CR1 + CD8α + DC. A PDC relationship of the cells is supported further by the fact that they harbor characteristic D–J Ig gene rearrangements and that development of CX 3 CR1 + CD8α + DC requires E2-2, the critical transcriptional regulator of PDC. Thus, CX 3 CR1 + CD8α + DC represent a unique DC subset, related to but distinct from PDC. Collectively, the expression-profiling data of this study refine the resolution of previous DC definitions, sharpen the border of classical CD8α + and CD8α − DC, and should assist the identification of human counterparts of murine DC subsets.
    Materialart: Online-Ressource
    ISSN: 0027-8424 , 1091-6490
    URL: Article
    DOI: 10.1073/pnas.1001562107
    RVK:
    TA 1000
    RVK:
    WA 15000
    Sprache: Englisch
    Verlag: Proceedings of the National Academy of Sciences
    Publikationsdatum: 2010
    ZDB Id: 209104-5
    ZDB Id: 1461794-8
    SSG: 11
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Online-Ressource
  • 10
    Online-Ressource
    Online-Ressource
    Robust nanoscopy of a synaptic protein in living mice by organic-fluorophore labeling
    Proceedings of the National Academy of Sciences ; 2018
    In:  Proceedings of the National Academy of Sciences Vol. 115, No. 34 ( 2018-08-21)
    Details
    In: Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 115, No. 34 ( 2018-08-21)
    Kurzfassung: Extending superresolution fluorescence microscopy to living animals has remained a challenging frontier ever since the first demonstration of STED (stimulated emission depletion) nanoscopy in the mouse visual cortex. The use of fluorescent proteins (FPs) in in vivo STED analyses has been limiting available fluorescence photon budgets and attainable image contrasts, in particular for far-red FPs. This has so far precluded the definition of subtle details in protein arrangements at sufficient signal-to-noise ratio. Furthermore, imaging with longer wavelengths holds promise for reducing photostress. Here, we demonstrate that a strategy based on enzymatic self-labeling of the HaloTag fusion protein by high-performance synthetic fluorophore labels provides a robust avenue to superior in vivo analysis with STED nanoscopy in the far-red spectral range. We illustrate our approach by mapping the nanoscale distributions of the abundant scaffolding protein PSD95 at the postsynaptic membrane of excitatory synapses in living mice. With silicon-rhodamine as the reporter fluorophore, we present imaging with high contrast and low background down to ∼70-nm lateral resolution in the visual cortex at ≤25-µm depth. This approach allowed us to identify and characterize the diversity of PSD95 scaffolds in vivo. Besides small round/ovoid shapes, a substantial fraction of scaffolds exhibited a much more complex spatial organization. This highly inhomogeneous, spatially extended PSD95 distribution within the disk-like postsynaptic density, featuring intricate perforations, has not been highlighted in cell- or tissue-culture experiments. Importantly, covisualization of the corresponding spine morphologies enabled us to contextualize the diverse PSD95 patterns within synapses of different orientations and sizes.
    Materialart: Online-Ressource
    ISSN: 0027-8424 , 1091-6490
    URL: Article
    DOI: 10.1073/pnas.1807104115
    RVK:
    TA 1000
    RVK:
    WA 15000
    Sprache: Englisch
    Verlag: Proceedings of the National Academy of Sciences
    Publikationsdatum: 2018
    ZDB Id: 209104-5
    ZDB Id: 1461794-8
    SSG: 11
    SSG: 12
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Online-Ressource
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...