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1.
Corey R. Nelson Tyler Mrozowich Sean M. Park Simmone Dsouza Amy Henrickson Justin R. J. Vigar Hans-Joachim Wieden Raymond J. Owens Borries Demeler Trushar R. Patel 《International journal of molecular sciences》2021,22(1)
Rift Valley fever virus (RVFV) is a mosquito-transmitted virus from the Bunyaviridae family that causes high rates of mortality and morbidity in humans and ruminant animals. Previous studies indicated that DEAD-box helicase 17 (DDX17) restricts RVFV replication by recognizing two primary non-coding RNAs in the S-segment of the genome: the intergenic region (IGR) and 5′ non-coding region (NCR). However, we lack molecular insights into the direct binding of DDX17 with RVFV non-coding RNAs and information on the unwinding of both non-coding RNAs by DDX17. Therefore, we performed an extensive biophysical analysis of the DDX17 helicase domain (DDX17135–555) and RVFV non-coding RNAs, IGR and 5’ NCR. The homogeneity studies using analytical ultracentrifugation indicated that DDX17135–555, IGR, and 5’ NCR are pure. Next, we performed small-angle X-ray scattering (SAXS) experiments, which suggested that DDX17 and both RNAs are homogenous as well. SAXS analysis also demonstrated that DDX17 is globular to an extent, whereas the RNAs adopt an extended conformation in solution. Subsequently, microscale thermophoresis (MST) experiments were performed to investigate the direct binding of DDX17 to the non-coding RNAs. The MST experiments demonstrated that DDX17 binds with the IGR and 5’ NCR with a dissociation constant of 5.77 ± 0.15 µM and 9.85 ± 0.11 µM, respectively. As DDX17135–555 is an RNA helicase, we next determined if it could unwind IGR and NCR. We developed a helicase assay using MST and fluorescently-labeled oligos, which suggested DDX17135–555 can unwind both RNAs. Overall, our study provides direct evidence of DDX17135–555 interacting with and unwinding RVFV non-coding regions. 相似文献
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Glycation of the Major Milk Allergen β‐Lactoglobulin Changes Its Allergenicity by Alterations in Cellular Uptake and Degradation 下载免费PDF全文
Marija Perusko Manon van Roest Dragana Stanic‐Vucinic Peter J. Simons Raymond H. H. Pieters Tanja Cirkovic Velickovic Joost J. Smit 《Molecular nutrition & food research》2018,62(17)
1 Scope
During food processing, the Maillard reaction (МR) may occur, resulting in the formation of glycated proteins. Glycated proteins are of particular importance in food allergies because glycation may influence interactions with the immune system. This study compared native and extensively glycated milk allergen β‐lactoglobulin (BLG), in their interactions with cells crucially involved in allergy.2 Methods and results
BLG was glycated in MR and characterized. Native and glycated BLG were tested in experiments of epithelial transport, uptake and degradation by DCs, T‐cell cytokine responses, and basophil cell degranulation using ELISA and flow cytometry. Glycation of BLG induced partial unfolding and reduced its intestinal epithelial transfer over a Caco‐2 monolayer. Uptake of glycated BLG by bone marrow–derived dendritic cells (BMDC) was increased, although both BLG forms entered BMDC via the same mechanism, receptor‐mediated endocytosis. Once inside the BMDC, glycated BLG was degraded faster, which might have led to observed lower cytokine production in BMDC/CD4+ T‐cells coculture. Finally, glycated BLG was less efficient in induction of degranulation of BLG‐specific IgE sensitized basophil cells.3 Conclusions
This study suggests that glycation of BLG by MR significantly alters its fate in processes involved in immunogenicity and allergenicity, pointing out the importance of food processing in food allergy. 相似文献6.
Sharma Nitin Kumar Kannan Rangasayee Li Leijun Anderson Neil Rashid Muhammad Collins Laurie Poplawsky Jonathan D. Unocic Raymond 《Metallurgical and Materials Transactions A》2021,52(9):3788-3798
Metallurgical and Materials Transactions A - The bondline of electric-resistance-welded (ERW) linepipe steel, often etched white (i.e., ferrite) in optical microscopy, is generally believed to be... 相似文献
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Garrett J. Meeks Raymond A. Cutler Dinesh K. Shetty 《Journal of the American Ceramic Society》2019,102(6):3771-3778
Phase-graded carbides that exhibit high hardness and corrosion resistance on the surface and high fracture toughness in the bulk are useful in severe wear applications. A method for producing hard γ-TaCy layer on the surface of a tough ζ-Ta4C3-x substrate by carburization is described in this study. The γ-TaCy layer exhibited parabolic growth kinetics in the temperature and gas-flow regimes investigated in this study. Analyses of the rate constants using a model of mass transport through two phases in equilibrium at the interface indicated diffusion of carbon through the product layer was the rate-controlling step with diffusivities (1-5 × 10−15 m2/s in the 1623-1773K range) and enthalpy (213-217 kJ/mol) matching those for carbon diffusion in γ-TaCy. Nanohardness of the transformed γ-TaCy layer increased as a function of distance from the carburized surface, with a maximum hardness occurring near the γ/ζ interface. Measurements of lattice parameters at different depths in the γ-TaCy layer indicated that the hardness increase with depth was related to the increasing carbon deficiency of the γ-TaCy phase through the thickness. 相似文献
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Scientometrics - Short communications are an integral part of academic journal publishing since they serve as a forum for scholarly debate on recently published journal articles. Their prestige and... 相似文献
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Sven Schlumpberger Raymond B. Smith Huanhuan Tian Ali Mani Martin Z. Bazant 《American Institute of Chemical Engineers》2021,67(8):e17274
Shock electrodialysis is a recently developed electrochemical water treatment method that shows promise for water deionization and ionic separations. Although simple models and scaling laws have been proposed, a predictive theory has not yet emerged to fit experimental data and enable system design. Here, we extend and analyze existing “leaky membrane” models for the canonical case of a steady shock in crossflow, as in recent experimental prototypes. Two-dimensional numerical solutions are compared with analytical boundary-layer approximations and experimental data. The boundary-layer theory accurately reproduces the simulation results for desalination, and both models predict the data collapse of the desalination factor with dimensionless current, scaled to the incoming convective flux of cations. The numerical simulation also predicts the water recovery increase with current. Nevertheless, neither approach can quantitatively fit the transition from normal to over-limiting current, which suggests gaps in our understanding of extreme electrokinetic phenomena in porous media. 相似文献