Recent developments have indicated that aminoglycoside binding is not limited to RNA, but to nucleic acids that, like RNA, adopt conformations similar to its A-form. We further sought to expand the utility of aminoglycoside binding to B-DNA structures by conjugating neomycin, an aminoglycoside antibiotic, with the B-DNA minor groove binding ligand Hoechst 33258. Envisioning a dual groove binding mode, we have extended the potential recognition process to include a third, intercalative moiety. Similar conjugates, which vary in the number of binding moieties but maintain identical linkages to allow direct comparisons to be made, have also been prepared. We report herein novel neomycin- and Hoechst 33258-based conjugates developed in our laboratories for exploring the recognition potential with B-DNA. Spectroscopic studies such as UV melting, differential scanning calorimetry, isothermal fluorescence titrations, and circular dichroism together illustrate the triple recognition of the novel conjugate containing neomycin, Hoechst 33258, and pyrene. This study represents the first example of DNA molecular recognition capable of minor versus major groove recognition in conjunction with intercalation.
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Mol Cell
January 2025
European Molecular Biology Laboratory (EMBL), EMBL Grenoble, 71 Avenue des Martyrs, 38042 Grenoble, France. Electronic address:
The minor spliceosome catalyzes excision of U12-dependent introns from precursors of eukaryotic messenger RNAs (pre-mRNAs). This process is critical for many cellular functions, but the underlying molecular mechanisms remain elusive. Here, we report a cryoelectron microscopy (cryo-EM) reconstruction of the 13-subunit human U11 small nuclear ribonucleoprotein particle (snRNP) complex in apo and substrate-bound forms, revealing the architecture of the U11 small nuclear RNA (snRNA), five minor spliceosome-specific factors, and the mechanism of the U12-type 5' splice site (5'SS) recognition.
View Article and Find Full Text PDFCancer Immunol Res
January 2025
Vanderbilt University, Nashville, TN, United States.
Tumor-specific HLA class I expression is required for cytotoxic T-cell elimination of cancer cells expressing tumor-associated or neo-antigens. Cancers downregulate antigen presentation to avoid adaptive immunity. The highly polymorphic nature of the genes encoding these proteins, coupled with quaternary-structure changes after formalin fixation, complicate detection by immunohistochemistry.
View Article and Find Full Text PDFCell Rep
January 2025
Department of Human Biology, Faculty of Natural Sciences, University of Haifa, Haifa 34988, Israel. Electronic address:
The elimination of superfluous neurons via apoptosis and subsequent glial phagocytosis is crucial for the development of the central nervous system (CNS). In Drosophila, two glial phagocytic receptors, six-microns-under (SIMU) and Draper, mediate the phagocytosis of apoptotic neurons during embryogenesis. However, in simu;draper double-mutant embryos, some apoptotic neurons are still engulfed by the glia, suggesting the involvement of additional receptors.
View Article and Find Full Text PDFJ Am Med Inform Assoc
January 2025
Division of Computational Health Sciences, Department of Surgery, University of Minnesota, Minneapolis, MN 55455, United States.
Objective: To develop an advanced multi-task large language model (LLM) framework for extracting diverse types of information about dietary supplements (DSs) from clinical records.
Methods: We focused on 4 core DS information extraction tasks: named entity recognition (2 949 clinical sentences), relation extraction (4 892 sentences), triple extraction (2 949 sentences), and usage classification (2 460 sentences). To address these tasks, we introduced the retrieval-augmented multi-task information extraction (RAMIE) framework, which incorporates: (1) instruction fine-tuning with task-specific prompts; (2) multi-task training of LLMs to enhance storage efficiency and reduce training costs; and (3) retrieval-augmented generation, which retrieves similar examples from the training set to improve task performance.
Immunology
January 2025
Graduate Institute of Immunology, College of Medicine, National Taiwan University, Taipei, Taiwan.
Enterovirus A71 (EV-A71) has caused hand, foot, and mouth disease with an increased prevalence of neurological complications and acute mortality, threatening young children around the globe. By provoking mucosal immunity, intranasal vaccination has been suggested to prevent EV-A71 infection. However, antigens delivered via the nasal route usually fail to induce a protective memory response.
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