{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\nSNORD86, a human intron‐hosted box C/D small nucleolar RNA, functions as a cis‐acting sensor and master switch for controlling levels of the core snoRNP protein NOP56. By adopting alternative ribonucleoprotein conformations, SNORD86 modulates alternative splice donor usage in the NOP56 pre‐mRNA. When excess snoRNP core proteins are present, this altered splicing triggers the generation of a cytoplasmic lncRNA through the nonsense‐mediated decay pathway, thereby establishing an autoregulatory feedback loop to ensure proper ribosome biogenesis and balanced snoRNA–protein stoichiometry."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": "\n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nPerforin-2, the product of the MPEG1 gene, is a pore-forming molecule that plays a crucial role in innate antibacterial defense. In interferon-stimulated fibroblasts as well as professional phagocytes, its upregulation correlates with the elimination of diverse intracellular bacteria. By inserting into bacterial membranes, perforin-2 creates pores that allow proteases and other antimicrobial effectors to access and degrade proteins sequestered within the bacterial envelope. This lethal hit mechanism limits the intracellular proliferation of pathogens such as Listeria monocytogenes and Salmonella, while also influencing the export of cytokines; for example, dendritic cell–derived IL-33 can be released via a perforin-2–dependent conduit, thereby modulating inflammatory and regulatory immune responses."}, {"type": "fg", "children": [{"type": "fg_fs", "start_ref": "2", "end_ref": "6"}]}, {"type": "t", "text": "\n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nIn addition to its direct microbicidal function, perforin-2 contributes to the coordination of innate and adaptive immunity. It is recruited to antigen-containing vesicles in dendritic cells, where its pore-forming activity facilitates the escape of internalized proteins into the cytosol—a key step in antigen cross-presentation and subsequent CD8+ T cell priming. Moreover, perforin-2 associates with components of the type I interferon receptor complex, promoting proper assembly of the receptor-proximal signaling machinery, and thus influences downstream JAK-STAT activation. Although some studies report conflicting observations regarding its overall impact on antibacterial and antiviral responses, this molecule appears to play a focused role early in the adaptive immune response, affecting both antigen presentation and the regulation of inflammatory cascades."}, {"type": "fg", "children": [{"type": "fg_fs", "start_ref": "7", "end_ref": "9"}]}, {"type": "t", "text": "\n"}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Søren Lykke-Andersen, Britt Kidmose Ardal, Anne Kruse Hollensen, et al. 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