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81.
82.
Ana R. Patrício Miguel R. Varela Castro Barbosa Annette C. Broderick Paulo Catry Lucy A. Hawkes Aissa Regalla Brendan J. Godley 《Global Change Biology》2019,25(2):522-535
Few studies have looked into climate change resilience of populations of wild animals. We use a model higher vertebrate, the green sea turtle, as its life history is fundamentally affected by climatic conditions, including temperature‐dependent sex determination and obligate use of beaches subject to sea level rise (SLR). We use empirical data from a globally important population in West Africa to assess resistance to climate change within a quantitative framework. We project 200 years of primary sex ratios (1900–2100) and create a digital elevation model of the nesting beach to estimate impacts of projected SLR. Primary sex ratio is currently almost balanced, with 52% of hatchlings produced being female. Under IPCC models, we predict: (a) an increase in the proportion of females by 2100 to 76%–93%, but cooler temperatures, both at the end of the nesting season and in shaded areas, will guarantee male hatchling production; (b) IPCC SLR scenarios will lead to 33.4%–43.0% loss of the current nesting area; (c) climate change will contribute to population growth through population feminization, with 32%–64% more nesting females expected by 2120; (d) as incubation temperatures approach lethal levels, however, the population will cease growing and start to decline. Taken together with other factors (degree of foraging plasticity, rookery size and trajectory, and prevailing threats), this nesting population should resist climate change until 2100, and the availability of spatial and temporal microrefugia indicates potential for resilience to predicted impacts, through the evolution of nest site selection or changes in nesting phenology. This represents the most comprehensive assessment to date of climate change resilience of a marine reptile using the most up‐to‐date IPCC models, appraising the impacts of temperature and SLR, integrated with additional ecological and demographic parameters. We suggest this as a framework for other populations, species and taxa. 相似文献
83.
Tremblay LO Nagy Kovács E Daniels E Wong NK Sutton-Smith M Morris HR Dell A Marcinkiewicz E Seidah NG McKerlie C Herscovics A 《The Journal of biological chemistry》2007,282(4):2558-2566
There are three mammalian Golgi alpha1,2-mannosidases, encoded by different genes, that form Man5GlcNAc2 from Man(8-9)GlcNAc2 for the biosynthesis of hybrid and complex N-glycans. Northern blot analysis and in situ hybridization indicate that the three paralogs display distinct developmental and tissue-specific expression. The physiological role of Golgi alpha1,2-mannosidase IB was investigated by targeted gene ablation. The null mice have normal gross appearance at birth, but they display respiratory distress and die within a few hours. Histology of fetal lungs the day before birth indicate some delay in development, whereas neonatal lungs show extensive pulmonary hemorrhage in the alveolar region. No significant histopathological changes occur in other tissues. No remarkable ultrastructural differences are detected between wild type and null lungs. The membranes of a subset of bronchiolar epithelial cells are stained with lectins from Phaseolus vulgaris (leukoagglutinin and erythroagglutinin) and Datura stramonium in wild type lungs, but this staining disappears in lungs from null mice. Mass spectrometry of N-glycans from different tissues shows no significant changes in global N-glycans of null mice. Therefore, only a few glycoproteins required for normal lung function depend on alpha1,2-mannosidase IB for maturation. There are no apparent differences in the expression of several lung epithelial cell and endothelial cell markers between null and wild type mice. The alpha1,2-mannosidase IB null phenotype differs from phenotypes caused by ablation of other enzymes in N-glycan biosynthesis and from other mouse gene disruptions that affect pulmonary development and function. 相似文献
84.
Cline MS Smoot M Cerami E Kuchinsky A Landys N Workman C Christmas R Avila-Campilo I Creech M Gross B Hanspers K Isserlin R Kelley R Killcoyne S Lotia S Maere S Morris J Ono K Pavlovic V Pico AR Vailaya A Wang PL Adler A Conklin BR Hood L Kuiper M Sander C Schmulevich I Schwikowski B Warner GJ Ideker T Bader GD 《Nature protocols》2007,2(10):2366-2382
Cytoscape is a free software package for visualizing, modeling and analyzing molecular and genetic interaction networks. This protocol explains how to use Cytoscape to analyze the results of mRNA expression profiling, and other functional genomics and proteomics experiments, in the context of an interaction network obtained for genes of interest. Five major steps are described: (i) obtaining a gene or protein network, (ii) displaying the network using layout algorithms, (iii) integrating with gene expression and other functional attributes, (iv) identifying putative complexes and functional modules and (v) identifying enriched Gene Ontology annotations in the network. These steps provide a broad sample of the types of analyses performed by Cytoscape. 相似文献
85.
Elizabeth F. Dowler Annette Diehl Peter Schmieder Christoph Brockmann Jonathan Elkins Meera Soundararajan Hartmut Oschkinat Linda J. Ball 《Biomolecular NMR assignments》2007,1(1):95-97
We have assigned 1H, 15N and 13C resonances of the RGS domain from the human RGS14 protein, a multi-domain member of the RGS (Regulators of G-protein signalling)
family of proteins, important in the down-regulation of specific G-protein signalling pathways. 相似文献
86.
Fina A. S Kurreeman Leonid Padyukov Rute B Marques Steven J Schrodi Maria Seddighzadeh Gerrie Stoeken-Rijsbergen Annette H. M van der Helm-van Mil Cornelia F Allaart Willem Verduyn Jeanine Houwing-Duistermaat Lars Alfredsson Ann B Begovich Lars Klareskog Tom W. J Huizinga Rene E. M Toes 《PLoS medicine》2007,4(12)
87.
Andersen Julie Høgsgaard Tjørnhøj-Thomsen Tine Reventlow Susanne Davidsen Annette Sofie 《Culture, medicine and psychiatry》2019,43(3):425-441
Culture, Medicine, and Psychiatry - An increasing number of young adults in Denmark experience difficulties in completing their education and holding down a job. Many of these young adults have... 相似文献
88.
Prasath Paramasivam Christian Franke Martin Stter Andreas Hijer Stefano Bartesaghi Alan Sabirsh Lennart Lindfors Marianna Yanez Arteta Anders Dahln Annette Bak Shalini Andersson Yannis Kalaidzidis Marc Bickle Marino Zerial 《The Journal of cell biology》2022,221(2)
Delivery of exogenous mRNA using lipid nanoparticles (LNPs) is a promising strategy for therapeutics. However, a bottleneck remains in the poor understanding of the parameters that correlate with endosomal escape versus cytotoxicity. To address this problem, we compared the endosomal distribution of six LNP-mRNA formulations of diverse chemical composition and efficacy, similar to those used in mRNA-based vaccines, in primary human adipocytes, fibroblasts, and HeLa cells. Surprisingly, we found that total uptake is not a sufficient predictor of delivery, and different LNPs vary considerably in endosomal distributions. Prolonged uptake impaired endosomal acidification, a sign of cytotoxicity, and caused mRNA to accumulate in compartments defective in cargo transport and unproductive for delivery. In contrast, early endocytic/recycling compartments have the highest probability for mRNA escape. By using super-resolution microscopy, we could resolve a single LNP-mRNA within subendosomal compartments and capture events of mRNA escape from endosomal recycling tubules. Our results change the view of the mechanisms of endosomal escape and define quantitative parameters to guide the development of mRNA formulations toward higher efficacy and lower cytotoxicity. 相似文献
89.
Stéphanie Finet Françoise Bonneté Jean Frouin Karine Provost Annette Tardieu 《European biophysics journal : EBJ》1998,27(3):263-271
A combination of small angle X-ray scattering and gel techniques was used to follow the kinetics of protein crystal growth
as a function of time. Hen egg white lysozyme, at different protein concentrations, was used as a model system. A new sample
holder was designed, in which supersaturation is induced in the presence of salt by decreasing the temperature. It had been
shown previously that a decrease in temperature and/or an increase in crystallizing agent induces an increase in the attractive
interactions present in the lysozyme solutions, the lysozyme remaining monomeric. In the present paper we show that similar
behaviour is observed in NaCl when agarose gels are used. During crystal growth, special attention was paid to determine whether
oligomers were formed as the protein in solution was incorporated in the newly formed crystals. From these first series of
experiments, we did not find any indication of oligomer formation between monomer in solution and crystal. The results obtained
are in agreement with the hypothesis that lysozyme crystals in NaCl grow by addition of monomeric particles.
Received: 28 July 1997 / Revised version: 4 December 1997 / Accepted: 5 December 1997 相似文献
90.
Bedoui S Miyake S Lin Y Miyamoto K Oki S Kawamura N Beck-Sickinger A von Hörsten S Yamamura T 《Journal of immunology (Baltimore, Md. : 1950)》2003,171(7):3451-3458
Prior studies have revealed that the sympathetic nervous system regulates the clinical and pathological manifestations of experimental autoimmune encephalomyelitis (EAE), an autoimmune disease model mediated by Th1 T cells. Although the regulatory role of catecholamines has been indicated in the previous works, it remained possible that other sympathetic neurotransmitters like neuropeptide Y (NPY) may also be involved in the regulation of EAE. Here we examined the effect of NPY and NPY receptor subtype-specific compounds on EAE, actively induced with myelin oligodendrocyte glycoprotein 35-55 in C57BL/6 mice. Our results revealed that exogenous NPY as well as NPY Y(1) receptor agonists significantly inhibited the induction of EAE, whereas a Y(5) receptor agonist or a combined treatment of NPY with a Y(1) receptor antagonist did not inhibit signs of EAE. These results indicate that the suppression of EAE by NPY is mediated via Y(1) receptors. Furthermore, treatment with the Y(1) receptor antagonist induced a significantly earlier onset of EAE, indicating a protective role of endogenous NPY in the induction phase of EAE. We also revealed a significant inhibition of myelin oligodendrocyte glycoprotein 35-55-specific Th1 response as well as a Th2 bias of the autoimmune T cells in mice treated with the Y(1) receptor agonist. Ex vivo analysis further demonstrated that autoimmune T cells are directly affected by NPY via Y(1) receptors. Taken together, we conclude that NPY is a potent immunomodulator involved in the regulation of the Th1-mediated autoimmune disease EAE. 相似文献