Let-7 microRNA (miRNA) regulates heterochronic genes in developmental timing of the nematode Caenorhabditis elegans. Binding of miRNA to messenger RNA (mRNA) and structural features of the complex are crucial for gene silencing. We herein present the NMR solution structure of a model mimicking the interaction of let-7 miRNA with its complementary site (LCS 2) in the 3' untranslated region (3'-UTR) of the lin-41 mRNA. A structural study was performed by NMR spectroscopy using NOE restraints, torsion angle restraints and residual dipolar couplings. The 33-nt RNA construct folds into a stem-loop structure that features two stem regions which are separated by an asymmetric internal loop. One of the stems comprises a GU wobble base pair, which does not alter its overall A-form RNA conformation. The asymmetric internal loop adopts a single, well-defined structure in which three uracils form a base triple, while two adenines form a base pair. The 3D structure of the construct gives insight into the structural aspects of interactions between let-7 miRNA and lin-41 mRNA.
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http://dx.doi.org/10.1093/nar/gkn088 | DOI Listing |
Inorg Chem
January 2025
Institute of Resource Ecology, Helmholtz-Zentrum Dresden-Rossendorf, Dresden 01328, Germany.
Heteroleptic An (An = U, Np) chlorido-ketoenaminate complexes of the type [AnCl(TFB-BuA)(THF)] ( type: , ; TFB-BuA = 4-(-butylamino)-1,1,1-trifluorobut-3-en-2-one) and the homoleptic Np heteroarylalkenolate complexes [Np(PyTFP)] (, PyTFP = 1-(pyridin-2-yl)-3,3,3-trifluoroprop-1-en-2-ol) and [Np(DMOTFP)] (, DMOTFP = 1-(4,5-dimethyloxazol-2-yl)-3,3,3-trifluoroprop-1-en-2-ol) were synthesized and characterized (SC-XRD, NMR, Vis-NIR, MS). While their solid-state structures compare well to those of their uranium analogues, the behavior in solution showed significant differences. The binding motif of the DMOTFP ligand in complex can change to form two different complex isomers, as seen by paramagnetic chemical shifts in NMR experiments.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
University of Regensburg, Faculty of Chemistry and Pharmacy, Institute of Inorganic Chemistry, Universitätsstraße 31, D-93053, Regensburg, GERMANY.
Aminophosphates are the focus of research on prebiotic phosphorylation chemistry. Their bifunctional nature also makes them a powerful class of organocatalysts. However, the structural chemistry and dynamics of proton-binding in phosphorylation and organocatalytic mechanisms are still not fully understood.
View Article and Find Full Text PDFAdv Mater
January 2025
State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou, 510275, China.
Terahertz (THz) signals are crucial for ultrawideband communication and high-resolution radar, demanding miniaturized detectors that can simultaneously measure multiple parameters such as intensity, frequency, polarization, and phase. Traditional detectors fail to meet these needs. To address this, we introduce a plasmon polariton atomic cavity (PPAC) detector based on monolayer graphene, offering a multifunctional, monolithic, and miniaturized solution.
View Article and Find Full Text PDFPLoS One
January 2025
School of Art and Design, Shenyang Aerospace University, Shenyang, China.
As urbanization intensifies and the need for sustainable transportation grows, Mobility as a Service (MaaS) emerges as a promising solution to urban mobility challenges. This study seeks to explore the underlying mechanisms of MaaS from a sustainability perspective and to assess its impact on service experience and user satisfaction. Additionally, it examines how user satisfaction influences the broader adoption of MaaS.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Department of Applied Chemistry, Chuo University, Tokyo 112-8551, Japan.
We employed machine learning (ML) techniques combined with potential-dependent photoelectrochemical impedance spectroscopy (pot-PEIS) to gain deeper insights into the charge transport mechanisms of hematite (α-FeO) photoanodes. By the Shapley Additive exPlanations (SHAP) analysis from the ML model constructed from a small data set (dozens of samples) of electrical parameters obtained from pot-PEIS and the PEC performance, we identified the dominant factors influencing the electron transport to the back contact in the bulk and hole transfer to a solution at the hematite/electrolyte interface. The results revealed that shallow defect states significantly enhance electron transport, while deep defect states impede it, and also one of the surface states enhances the hole transfer to the electrolyte solution.
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