An allosteric ribozyme that requires two different effectors to induce catalysis was created using modular rational design. This ribozyme construct comprises five conjoined RNA modules that operate in concert as an obligate FMN- and theophylline-dependent molecular switch. When both effectors are present, this 'binary' RNA switch self-cleaves with a rate enhancement of approximately 300-fold over the rate observed in the absence of effectors. Kinetic and structural studies implicate a switching mechanism wherein FMN binding induces formation of the active ribozyme conformation. However, the binding site for FMN is rendered inactive unless theophylline first binds to its corresponding site and reorganizes the RNA structure. This example of cooperative binding between allosteric effectors reveals a level of structural and functional complexity for RNA that is similar to that observed with allosteric proteins.
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http://dx.doi.org/10.1093/nar/29.7.1631 | DOI Listing |
J Mol Biol
January 2025
Department of Applied Bioscience, Kanazawa Institute of Technology. Electronic address:
A variety of potential biological roles of mechanical forces have been proposed in the field of cell biology. In particular, mechanical forces alter the mechanical conditions within cells and their environment, exerting a strong effect on the reorganization of the actin cytoskeleton. Single-molecule imaging studies have provided evidence that an actin filament may act as a mechanosensor.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
Chinese-German Joint Laboratory for Natural Product Research, Shaanxi International Cooperation Demonstration Base, Shaanxi University of Technology, Hanzhong, Shaanxi 723000, China; Centre of Molecular & Environmental Biology, Department of Biology, University of Minho, Braga 4710-057, Portugal; Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, Ontario N1G 2W1, Canada. Electronic address:
The increasing environmental prevalence of micro/nano plastics (MNPs) has raised significant concerns regarding their potential impact on human health, particularly in terms of immunotoxicity. However, the direct effects of MNPs on immune molecules, especially how they may influence protein liquid-liquid phase separation (LLPS)-a critical process implicated in various aspects of immune function-remain largely unexplored. This study addresses this gap by investigating the effects of polystyrene nanoparticles (PS NPs) with different surface modifications and sizes on LLPS in immunoglobulin Y (IgY) antibodies, critical components of the avian immune system.
View Article and Find Full Text PDFLangmuir
January 2025
School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China.
The antifreeze mechanism of antifreeze glycoproteins (AFGPs) remains incompletely understood, which limits the design of new antifreeze molecules for practical applications. For instance, the ice growth inhibition of AFGP8 (the shortest AFGPs) is primarily driven by hydrophobic methyl and hydrogen-bonding hydroxyl groups. However, altering the C3-β linkage in the disaccharide moiety of AFGP8, denoted as variant GP8-LacNAc, significantly reduces its antifreeze activity.
View Article and Find Full Text PDFVirulence
December 2025
National Key Laboratory of Agricultural Microbiology, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, China.
The emergence of antibiotic-resistant bacteria has attracted interest in the field of endolysins. Here, we analyzed the diversity of endolysins and identified a new endolysin, Ply2741, that exhibited broad-spectrum bactericidal activity. Our results demonstrated that Ply2741 could effectively eradicate multidrug-resistant gram-positive pathogens and .
View Article and Find Full Text PDFNat Commun
January 2025
National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, People's Republic of China.
The Eurasian avian-like (EA) H1N1 swine influenza virus (SIV) possesses the capacity to instigate the next influenza pandemic, owing to its heightened affinity for the human-type α-2,6 sialic acid (SA) receptor. Nevertheless, the molecular mechanisms underlying the switch in receptor binding preferences of EA H1N1 SIV remain elusive. In this study, we conduct a comprehensive genome-wide CRISPR/Cas9 knockout screen utilizing EA H1N1 SIV in porcine kidney cells.
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