Initiation of translation at the correct position on messenger RNA is essential for accurate protein synthesis. In prokaryotes, this process requires three initiation factors: IF1, IF2, and IF3. Here we report the crystal structure of a complex of IF1 and the 30S ribosomal subunit. Binding of IF1 occludes the ribosomal A site and flips out the functionally important bases A1492 and A1493 from helix 44 of 16S RNA, burying them in pockets in IF1. The binding of IF1 causes long-range changes in the conformation of H44 and leads to movement of the domains of 30S with respect to each other. The structure explains how localized changes at the ribosomal A site lead to global alterations in the conformation of the 30S subunit.
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http://dx.doi.org/10.1126/science.1057766 | DOI Listing |
Science
January 2025
Department of Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
Phase diagrams and crystallography are standard tools for studying structural phase transitions, whereas acquiring kinetic information at the atomistic level has been considered essential but challenging. The η-to-θ phase transition of alumina is unidirectional in bulk and retains the crystal lattice orientation. We report a rare example of a statistical kinetics study showing that for nanoparticles on a bulk Al(OH) surface, this phase transition occurs nondeterministically through an ergodic equilibrium through the molten state, and the memory of the lattice orientation is lost in this process.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
National Engineering Research Center for Advanced Polymer Processing Technology, Key Laboratory of Materials Processing and Mold of Zhengzhou University, Zhengzhou 450000, China.
Planar 1D photonic crystals (1DPhCs), owing to their photonic bandgaps (PBGs) formed by unique structural interference, are widely utilized in light protection applications. Multifunctional coatings that integrate various light management functions are highly desired. In this study, we present the fabrication of dual-PBG 1DPhCs with high reflectance in both the blue and near-infrared (NIR) regions.
View Article and Find Full Text PDFNano Converg
January 2025
Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 29 Geumgu-gil, Jeongeup-si, Jeolabuk-do, 56212, Republic of Korea.
Metal-oxide thin-film semiconductors have been highlighted as next-generation space semiconductors owing to their excellent radiation hardness based on their dimensional advantages of very low thickness and insensitivity to crystal structure. However, thin-film transistors (TFTs) do not exhibit intrinsic radiation hardness owing to the chemical reactions at the interface exposed to ambient air. In this study, significantly enhanced radiation hardness of AlO-passivated ZnO TFTs against high-energy protons with energies of up to 100 MeV is obtained owing to the passivation layer blocking interactions with external reactants, thereby maintaining the chemical stability of the thin-film semiconductor.
View Article and Find Full Text PDFMAbs
December 2025
Ichnos Glenmark Innovation, New York, NY, USA.
ISB 1442 is a bispecific biparatopic antibody in clinical development to treat hematological malignancies. It consists of two adjacent anti-CD38 arms targeting non-overlapping epitopes that preferentially drive binding to tumor cells and a low-affinity anti-CD47 arm to enable avidity-induced blocking of proximal CD47 receptors. We previously reported the pharmacology of ISB 1442, designed to reestablish synthetic immunity in CD38+ hematological malignancies.
View Article and Find Full Text PDFBiochemistry
January 2025
Department of Biosciences and Bioengineering, Indian Institute of Technology, Roorkee, Uttarakhand 247667, India.
SARS-CoV-2 variant recurrence has emphasized the imperative prerequisite for effective antivirals. The main protease (Mpro) of SARS-CoV-2 is crucial for viral replication, making it one of the prime and promising antiviral targets. Mpro features several druggable sites, including active sites and allosteric sites near the dimerization interface, that regulate its catalytic activity.
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