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Biology subjects

Yang, Y.

Publications and source records attributed to Yang, Y..

At least 703 records · Page 39Linked to original sources

ZNF397 Loss Triggers TET2-driven Epigenetic Rewiring, Lineage Plasticity, and AR-targeted Therapy Resistance in AR-dependent Cancers

Cancer cells exhibit phenotypical plasticity and epigenetic reprogramming, which allows them to evade lineage-dependent targeted treatments by adopting lineage plasticity. The underlying mechanisms by which cancer cells exploit the epigenetic regulatory machinery to acquire lineage plasticity and therapy resistance remain poorly understood. We identified Zinc Finger Protein 397 (ZNF397) as a bona fide co-activator of the androgen receptor (AR), essential for the transcriptional program governing AR-driven luminal lineage. ZNF397 deficiency facilitates the transition of cancer cell from an AR-driven luminal lineage to a Ten-Eleven Translocation 2 (TET2)-driven lineage plastic state, ultimately promoting resistance to therapies inhibiting AR signaling. Intriguingly, our findings indicate that TET2 inhibitor can eliminate the AR targeted therapies resistance in ZNF397-deficient tumors. These insights uncover a novel mechanism through which prostate and breast cancers acquire lineage plasticity via epigenetic rewiring and offer promising implications for clinical interventions designed to overcome therapy resistance dictated by lineage plasticity. Statement of SignificanceThis study reveals a novel epigenetic mechanism regulating tumor lineage plasticity and therapy response, enhances understanding of drug resistance and unveils a new therapeutic strategy for prostate cancer and other malignancies. Our findings also illuminate TET2s oncogenic role and mechanistically connect TET2-driven epigenetic rewiring to lineage plasticity and therapy resistance.

cancer biology↗

A Spatiotemporal and Machine-Learning Platform Accelerates the Manufacturing of hPSC-derived Esophageal Mucosa

Human pluripotent stem cell-derived tissue engineering offers great promise in designer cell-based personalized therapeutics. To harness such potential, a broader approach requires a deeper understanding of tissue-level interactions. We previously developed a manufacturing system for the ectoderm-derived skin epithelium for cell replacement therapy. However, it remains challenging to manufacture the endoderm-derived esophageal epithelium, despite both possessing similar stratified structure. Here we employ single cell and spatial technologies to generate a spatiotemporal multi-omics cell atlas for human esophageal development. We illuminate the cellular diversity, dynamics and signal communications for the developing esophageal epithelium and stroma. Using the machine-learning based Manatee, we prioritize the combinations of candidate human developmental signals for in vitro derivation of esophageal basal cells. Functional validation of the Manatee predictions leads to a clinically-compatible system for manufacturing human esophageal mucosa. Our approach creates a versatile platform to accelerate human tissue manufacturing for future cell replacement therapies to treat human genetic defects and wounds.

developmental biology↗

Expression of Filaments of the Geobacter Extracellular Cytochrome OmcS in Shewanella oneidensis

The physiological role of Geobacter sulfurreducens extracellular cytochrome filaments is a matter of debate and the development of proposed electronic device applications of cytochrome filaments awaits methods for large-scale cytochrome nanowire production. Functional studies in Geobacter sulfurreducens are stymied by the broad diversity of redox-active proteins on the outer cell surface and the redundancy and plasticity of extracellular electron transport routes. G. sulfurreducens is a poor chassis for producing cytochrome nanowires for electronics because of its slow, anaerobic growth. Here we report that filaments of the G. sulfurreducens cytochrome OmcS can be heterologously expressed in Shewanella oneidensis. Multiple lines of evidence demonstrated that a strain of S. oneidensis, expressing the G. sulfurreducens OmcS gene on a plasmid, localized OmcS on the outer cell surface. Atomic force microscopy revealed filaments with the unique morphology of OmcS filaments emanating from cells. Electron transfer to OmcS appeared to require a functional outer-membrane porin-cytochrome conduit. The results suggest that S. oneidensis, which grows rapidly to high culture densities under aerobic conditions, may be a suitable for development of a chassis for producing cytochrome nanowires for electronics applications and may also be good model microbe for elucidating cytochrome filament function in anaerobic extracellular electron transfer.

synthetic biology↗

Endothelial Cell Serum and Glucocorticoid Regulated Kinase 1 (SGK1) Mediates Vascular Stiffening

BackgroundExcess dietary salt increases vascular stiffness in humans, especially in salt- sensitive populations. While we recently suggested that the endothelial sodium channel (EnNaC) contributes to salt-sensitivity related endothelial cell (EC) and arterial stiffening, mechanistic understanding is incomplete. This study thus aimed to explore the role of EC-serum and glucocorticoid regulated kinase 1 (SGK1), as a regulator of sodium channels, in EC and arterial stiffening. Methods and ResultsA mouse model of salt sensitivity-associated vascular stiffening was produced by subcutaneous implantation of slow-release deoxycorticosterone acetate (DOCA) pellets, with salt (1% NaCl, 0.2% KCl) administered via drinking water. Preliminary data showed that global SGK1 deletion caused significantly decreased blood pressure, EnNaC activity and aortic endothelium stiffness as compared to control mice following DOCA-salt treatment. To probe EC signaling pathways, selective deletion of EC-SGK1 was performed by cross-breeding cadherin 5-Cre mice with sgk1flox/flox mice. DOCA-salt treated control mice had significantly increased blood pressure, EC and aortic stiffness in vivo and ex vivo, which were attenuated by EC-SGK1 deficiency. To demonstrate relevance to humans, human aortic ECs were cultured in the absence or presence of aldosterone and high salt with or without the SGK1 inhibitor, EMD638683 (10uM or 25uM). Treatment with aldosterone and high salt increased intrinsic stiffness of ECs, which was prevented by SGK1 inhibition. Further, the SGK1 inhibitor prevented aldosterone and high salt induced actin polymerization, a key mechanism in cellular stiffening. ConclusionEC-SGK1 mediates salt-sensitivity related EC and aortic stiffening by mechanisms appearing to involve regulation actin polymerization. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=125 SRC="FIGDIR/small/563167v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@74497forg.highwire.dtl.DTLVardef@855709org.highwire.dtl.DTLVardef@151c72org.highwire.dtl.DTLVardef@1feae92_HPS_FORMAT_FIGEXP M_FIG C_FIG

physiology↗

Co-existence of blaKPC-2 and blaVIM-2 in highly carbapenem-resistant Pseudomonas aeruginosa isolated in the ICU of a public hospital

In this study, highly carbapenem-resistant Pseudomonas aeruginosa (h-CRPA) 18102011 [the minimum inhibitory concentration (MIC) value of carbapenem antimicrobial imipenem (IP) for h-CRPA is 4,096 g/mL] was isolated from the bile of an intensive care unit (ICU) burn patient in China, and genomic sequencing revealed a complete genome. The genomes molecular characteristics were analyzed to assess the genetic environment of blaKPC-2 and blaVIM-2. Average nucleotide identity (ANI) comparisons were used for precise species-level identification, while serotyping, multi-locus sequence typing, and the identification of acquired resistance genes, and virulence genes were also carried out. The h-CRPA 18102011 strain carrying blaKPC-2 and blaVIM-2 was identified as strain ST2374 and the O4 serotype. Virulence genes (plcH, exoST) and resistance genes (aph(3)-IIb, aac(6)-Ib-cr, ant(2)-Ia, blaOXA-396, blaPAO, blaKPC-2, blaVIM-2, blaPER-1, sul1, catB7, qnrVC6, fosA) were both identified in the genome. In addition, the IncpRBL16 type mega-plasmid pP2011-1 carrying blaVIM-2 and the IncP6 type plasmid pP2011-2 carrying blaKPC-2 were identified in the strain. The genetic environment of blaVIM-2 and blaKPC-2 was specifically evaluated to assess their origins. blaVIM-2 was located in the region of In2075 (a novel type 1 integron) that was inserted into plasmid pP2011-1, this plasmid contained 3 novel recombination sites, as well as the typical recombination site 2 (umuC) observed for IncpRBL16 type plasmids. However, the core module Tn3-ISKpn27-blaKPC-{Delta}ISKpn6 was identified as the blaKPC-2 platform in plasmid pP2011-2. Conjugation experiments revealed that the plasmids pP2011-1 and pP2011-2 of the h-CRPA 18102011 strain could be transferred into Escherichia coli with a conjugation transfer efficiency of 10-6. The E. coli transconjugant carried blaKPC-2 and blaVIM-2 from the donor and the MIC value of IP to the E. coli transconjugant was 4,096 g/mL, which was the same as observed for the donor. Overall, this study revealed the molecular characteristics of a VIM-2 and KPC-2-co-producing strain that was typed as O4 and ST2374. The continuous monitoring of bacteria, such as the strain investigated here, that co-harbor different types of carbapenemase genes is critical for preventing the spread of these genes.

genomics↗

Trans-Lesion Synthesis and Mismatch Repair Pathway Crosstalk Defines Chemoresistance and Hypermutation Mechanisms in Glioblastoma

Almost all Glioblastoma (GBM) are either intrinsically resistant to the chemotherapeutical drug temozolomide (TMZ) or acquire therapy-induced mutations that cause chemoresistance and recurrence. The genome maintenance mechanisms responsible for GBM chemoresistance and hypermutation are unknown. We show that the E3 ubiquitin ligase RAD18 (a proximal regulator of TLS) is activated in a Mismatch repair (MMR)-dependent manner in TMZ-treated GBM cells, promoting post-replicative gap-filling and survival. An unbiased CRISPR screen provides a new aerial map of RAD18-interacting DNA damage response (DDR) pathways deployed by GBM to tolerate TMZ genotoxicity. Analysis of mutation signatures from TMZ-treated GBM reveals a role for RAD18 in error-free bypass of O6mG (the most toxic TMZ-induced lesion), and error-prone bypass of other TMZ-induced lesions. Our analyses of recurrent GBM patient samples establishes a correlation between low RAD18 expression and hypermutation. Taken together we define novel molecular underpinnings for the hallmark tumorigenic phenotypes of TMZ-treated GBM.

cancer biology↗

DiffDec: Structure-Aware Scaffold Decoration with an End-to-End Diffusion Model

In molecular optimization, one popular way is R-groups decoration on molecular scaffolds, and many efforts have been put to generate R-groups based on deep generative models. However, these methods mostly use information of known binding ligands, without fully utilizing target structure information. In this study, we proposed a new method, DiffDec, to involve three-dimensional pocket constraints by a modified diffusion technique for optimizing molecules through molecular scaffold decoration. For an end-to-end generation of R-groups with different sizes, we designed a novel fake atom mechanism. DiffDec was shown able to generate structure-aware R-groups, and simultaneously generate multiple R-groups for one scaffold on different growth anchors. The growth anchors could be provided by users or automatically determined by our model. DiffDec achieved R-group recovery rates of 69.67% and 45.34% in the single and multiple R-group decoration tasks, respectively, and these values were significantly higher than competing methods (37.33% and 26.85%). According to the molecular docking study, our decorated molecules obtained better average binding affinity than baseline methods. The docking pose analysis revealed that DiffDec could decorate scaffolds with R-groups that exhibited improved binding affinities and more favourable interactions with the pocket. These results demonstrated the potential and applicability of DiffDec in real-world scaffold decoration for molecular optimization.

bioinformatics↗

Identification of CFAP52 as a novel diagnostic target of male infertility with defects of sperm head-tail connection and flagella development

Male infertility is a worldwide population health concern. Asthenoteratozoospermia is a common cause of male infertility, but its etiology remains incompletely understood. No evidence indicates the relevance of CFAP52 mutations to human male infertility. Our whole-exome sequencing identified compound heterozygous mutations in CFAP52 recessively cosegregating with male infertility status in a non-consanguineous Chinese family. Spermatozoa of CFAP52-mutant patient mainly exhibited abnormal head-tail connection and deformed flagella. Cfap52-knockout mice resembled the human infertile phenotype, showing a mixed acephalic spermatozoa syndrome (ASS) and multiple morphological abnormalities of the sperm flagella (MMAF) phenotype. The ultrastructural analyses further revealed a failure of connecting piece formation and a serious disorder of 9+2 axoneme structure. CFAP52 interacts with a head-tail coupling regulator SPATA6 and is essential for its stability. Expression of microtubule inner proteins and radial spoke proteins were reduced after the CFAP52 deficiency. Moreover, CFAP52-associated male infertility in humans and mice could be overcome by ICSI. The study reveals a prominent role for CFAP52 in sperm development, suggesting that CFAP52 might be a novel diagnostic target for male infertility with defects of sperm head-tail connection and flagella development

genetics↗

G protein subunit Gγ13-mediated signaling pathway is critical to the inflammation resolution and functional recovery of severely injured lungs

Tuft cells are a group of rare epithelial cells that can detect pathogenic microbes and parasites. Many of these cells express signaling proteins initially found in taste buds. It is, however, not well understood how these taste signaling proteins contribute to the response to the invading pathogens or to the recovery of injured tissues. In this study, we conditionally nullified the signaling G protein subunit G{gamma}13 and found that the number of ectopic tuft cells in the injured lung was reduced following the infection of the influenza virus H1N1. Furthermore, the infected mutant mice exhibited significantly larger areas of lung injury, increased macrophage infiltration, severer pulmonary epithelial leakage, augmented pyroptosis and cell death, greater bodyweight loss, slower recovery, worsened fibrosis and increased fatality. Our data demonstrate that the G{gamma}13-mediated signal transduction pathway is critical to tuft cells-mediated inflammation resolution and functional repair of the damaged lungs.To our best knowledge, it is the first report indicating subtype-specific contributions of tuft cells to the resolution and recovery.

immunology↗

Amur grape genome sequence

To date, there is no high-quality sequence for genomes of the East Asian grape species, hindering biological and breeding research efforts to improve grape cultivars. This study presents a [~]522 Mb of the Vitis amurensis (Va) genome sequence containing 27,635 coding genes. Phylogenetic analysis indicated that V. riparia (Vr) may firstly split from the other two species, Va, V. Vinifera (Vv; Pinot Noir: PN40024 and Cabernet Sauvignon). Much divergent gene reservation among three grape duplicated gene sets suggests that the core eudicot common hexaploidy (ECH), 130 million years ago (Mya), has still played a non-negligible role in grape species divergence and biological innovation. Prominent accumulation of sequence variants might have improved cold resistance in Va, resulting in a more robust cold resistance gene regulatory network than those in Vv and Vr. In contrast, Va preserved much fewer NBS disease resistance genes than the other grapes. Notably, multi-omics analysis identified one trans-cinnamate 4-monooxygenase gene positively correlated to the resveratrol accumulated during Va berry development. A selective sweep analysis revealed a hypothetical Va sex-determination region (SDR). Besides, a PPR-containing protein-coding gene in the hypothetical SDR may be related with sex determination in Va. The content and arrangement order of genes in the putative SDR of female Va were similar to the SDR of female Vv. However, the putative SDR of female Va lost one Flavin-containing monooxygenases (FMO) and contained one extra uncharacterized protein-coding gene. These findings will improve the understanding of Vitis biology and contribute to the improvement of grape breeding.

genomics↗

In vivo disentanglement of diffusion frequency-dependence, tensor shape, and relaxation using multidimensional MRI

Diffusion MRI with free gradient waveforms, combined with simultaneous relaxation encoding, referred to as multidimensional MRI (MD-MRI), offers microstructural specificity in complex biological tissue. This approach delivers intravoxel information about the microstructure, local chemical composition, and importantly, how these properties are coupled within heterogeneous tissue containing multiple microenvironments. Recent theoretical advances incorporated diffusion time dependency and integrated MD-MRI with concepts from oscillating gradients. This framework probes the diffusion frequency,{omega} , in addition to the diffusion tensor, D, and relaxation, R1, R2, correlations. A D({omega})-R1-R2 clinical imaging protocol was then introduced, with limited brain coverage and 3 mm3 voxel size, which hinder brain segmentation and future cohort studies. In this study, we introduce an efficient, sparse in vivo MD-MRI acquisition protocol providing whole brain coverage at 2 mm3 voxel size. We demonstrate its feasibility and robustness using a well-defined phantom and repeated scans of five healthy individuals. Additionally, we test different denoising strategies to address the sparse nature of this protocol, and show that efficient MD-MRI encoding design demands a nuanced denoising approach. The MD-MRI framework provides rich information that allows resolving the diffusion frequency dependence into intravoxel components based on their D({omega})-R1-R2 distribution, enabling the creation of microstructure-specific maps in the human brain. Our results encourage the broader adoption and use of this new imaging approach for characterizing healthy and pathological tissues.

neuroscience↗

Potential intrahospital dissemination of Pseudomonas aeruginosa carrying the blaIMP-1 gene within a Tn7-like transposon

We aimed to determine the molecular characteristics of carbapenem-resistant Pseudomonas aeruginosa 18081308 and 18083286 isolated from the urine and sputum of two Chinese patients respectively, and analyzed the formation mechanism of the genetic environment in which it carries blaIMP-1. Bacterial genome sequencing was carried out on strains 18081308 and 18083286 to obtain their whole genome sequence. Average nucleotide identity (ANI) was used for their precise species identification. Serotyping and multilocus sequence typing were performed. Furthermore, the acquired resistance genes, and virulence factors of these strains were identified. The carbapenem-resistant P. aeruginosa strains isolated in the present study were of sequence type ST865 and serotype O6. They all carried the same virulence factors (PLC, ExoSTY) and resistance genes (aacC2, tmrB, and blaIMP-1). Tn6411, a Tn7-like transposon carrying blaIMP-1, was found in both strains. Detailed genetic dissection was applied to this transposon to display the genetic environment of blaIMP-1. The aacC2-tmrB region remnant-Tn6411 backbone was the original structure of this type of transposon. A Tn402-like type 1 integron (intl1-aac(6)-II-blaIMP-1) was inserted into it and formed a stable structure, which was localized in the chromosome by TnsD for transmission within P. aeruginosa; the original structure of Tn7-like transposon was localized on the plasmid by TnsE for horizontal transmission between bacterial species. The intrahospital dissemination of P. aeruginosa ST865 isolated in this study was episodic. The blaIMP-1-carrying Tn7-like transposon might enhance their ability to survive under drug selection pressure and aggravate the difficulty in treating infections.

genomics↗

Cryo-EM structures of Aβ40 filaments from the leptomeninges of individuals with Alzheimer's disease and cerebral amyloid angiopathy

We used electron cryo-microscopy (cryo-EM) to determine the structures of A{beta}40 filaments from the leptomeninges of individuals with Alzheimers disease and cerebral amyloid angiopathy. In agreement with previously reported structures, which were solved to a resolution of 4.4 [A], we found three types of filaments. However, our new structures, solved to a resolution of 2.4 [A] resolution, revealed differences in the sequence assignment that redefine the fold of A{beta}40 peptides and their interactions. Filaments are made of pairs of protofilaments, the ordered core of which comprises D1-G38. The different filament types comprise one, two or three protofilament pairs. In each pair, residues H14-G37 of both protofilaments adopt an extended conformation and pack against each other in an anti-parallel fashion, held together by hydrophobic interactions and hydrogen bonds between main chains and side chains. Residues D1-H13 fold back on the adjacent parts of their own chains through both polar and non-polar interactions. There are also several additional densities of unknown identity. Sarkosyl extraction and aqueous extraction gave the same structures. By cryo-EM, parenchymal deposits of A{beta}42 and blood vessel deposits of A{beta}40 have distinct structures, supporting the view that Alzheimers disease and cerebral amyloid angiopathy are different A{beta} proteinopathies.

neuroscience↗

Intrinsic forebrain arousal dynamics governs sensory stimulus encoding

The neural encoding of sensory stimuli is subject to the brains internal circuit dynamics. Recent work has demonstrated that the resting brain exhibits widespread, coordinated activity that plays out over multisecond timescales in the form of quasi-periodic spiking cascades. Here we demonstrate that these intrinsic dynamics persist during the presentation of visual stimuli and markedly influence the efficacy of feature encoding in the visual cortex. During periods of passive viewing, the sensory encoding of visual stimuli was determined by quasi-periodic cascade cycle evolving over several seconds. During this cycle, high efficiency encoding occurred during peak arousal states, alternating in time with hippocampal ripples, which were most frequent in low arousal states. However, during bouts of active locomotion, these arousal dynamics were abolished: the brain remained in a state in which visual coding efficiency remained high and ripples were absent. We hypothesize that the brains observed dynamics during awake, passive viewing reflect an adaptive cycle of alternating exteroceptive sensory sampling and internal mnemonic function.

neuroscience↗

Fabrication of Crescent Shaped Microparticles for Particle Templated Droplet Formation

Crescent-shaped hydrogel microparticles have been shown to template uniform volume aqueous droplets upon simple mixing with aqueous and oil media for various bioassays. This emerging "lab on a particle" technique requires hydrogel particles with tunable material properties and dimensions. The crescent shape of the particles is attained by aqueous two-phase separation of polymers inside a spherical droplet followed by photopolymerization of the curable precursor. In this work, we have investigated the phase separation of photo-curable poly(ethylene glycol) diacrylate (PEGDA, Mw 700) and dextran (Mw 40,000) for tunable manufacturing of crescent-shaped particles. The particles morphology was precisely tuned by following a phase diagram, varying the UV intensity, and adjusting the flow rate ratio between the three streams, containing PEGDA, dextran, and oil, within a microfluidic droplet generation device. The fabricated particles with variable cavity sizes and outer diameters encapsulated uniform aqueous droplets upon mixing with a continuous oil phase. The particles were fluorescently labeled with red and blue emitting dyes at variable concentrations to produce six color-coded particles. The blue fluorescent dye showed a moderate response to the pH change from 1 to 7 in terms of an increase in emitted intensity. The fluorescently labeled particles were able to tolerate an extremely acidic solution (pH 1) but disintegrated within an extremely basic solution (pH 14). The particle-templated droplets were able to effectively retain the disintegrating particle and the fluorescent signal at pH 14, indicating completely segregated compartments.

bioengineering↗

Systematic Investigation of Machine Learning on Limited Data: A Study on Predicting Protein-Protein Binding Strength

The application of machine learning techniques in biological research, especially when dealing with limited data availability, poses significant challenges. In this study, we leveraged advancements in method development for predicting protein-protein binding strength to conduct a systematic investigation into the application of machine learning on limited data. The binding strength, quantitatively measured as binding affinity, is vital for understanding the processes of recognition, association, and dysfunction that occur within protein complexes. By incorporating transfer learning, integrating domain knowledge, and employing both deep learning and traditional machine learning algorithms, we mitigate the impact of data limitations and make significant advancements in predicting protein-protein binding affinity. In particular, we developed over 20 models, ultimately selecting three representative best-performing ones that belong to distinct categories. The first model is structure-based, consisting of a random forest regression and thirteen handcrafted features. The second model is sequence-based, employing an architecture that combines transferred embedding features with a multilayer perceptron. Finally, we created an ensemble model by averaging the predictions of the two aforementioned models. The comparison with other predictors on three independent datasets confirmed the significant improvements achieved by our models in predicting protein-protein binding affinity. The source codes for these three models are available at https://github.com/minghuilab/BindPPI.

bioinformatics↗

Compression of sickspan by interventions that steepen the survival curve

Longevity research aims to extend the period of healthy life, known as the healthspan, and to minimize the duration of disability and morbidity, known as the sickspan. Most longevity interventions in model organisms extend healthspan, but it is not known whether they extend healthspan relative to the lifespan - that is, whether they compress relative sickspan. Here, we present a theory that predicts which interventions effectively compress relative sickspan. The theory is based on the shape of the survival curve - the fraction of organisms surviving as a function of age. Interventions that extend mean lifespan while preserving the shape of the survival curve, known as scaling, are predicted to extend the sickspan proportionally, without compressing it. Such interventions include caloric restriction and many other longevity interventions. Conversely, a small subset of interventions that extend lifespan and steepen the shape of the survival curve, are predicted to compress the relative sickspan. We explain this based on the saturating removal mathematical model of aging, and present evidence from longitudinal health data in mice, Caenorhabditis elegans and Drosophila melanogaster. We discuss longevity interventions in mice that steepen the survival curves, including senolytics, ketogenic diet, and agents that reduce glucose spikes and protect blood vessels, as potential candidates for compressing the sickspan. We apply the theory to combinations of longevity interventions and discuss human healthspan data. This approach offers potential strategies for compressing morbidity and extending healthspan.

systems biology↗

SARS-CoV-2 N protein-induced Dicer, XPO5, SRSF3, and hnRNPA3 downregulation causes pneumonia

Age is a major risk factor for coronavirus disease (COVID-19)-associated severe pneumonia and mortality; however, the underlying mechanism remains unclear. Herein, we investigated whether age-related deregulation of RNAi components and RNA splicing factors affects COVID-19 severity. Decreased expression of RNAi components (Dicer and XPO5) and splicing factors (SRSF3 and hnRNPA3) correlated with increased severity of COVID-19 and SARS-CoV-2 nucleocapsid (N) protein-induced pneumonia. N protein induced autophagic degradation of Dicer, XPO5, SRSF3, and hnRNPA3, repressing miRNA biogenesis and RNA splicing and inducing DNA damage, proteotoxic stress, and pneumonia. Dicer, XPO5, SRSF3, and hnRNPA3 were downregulated with age in mouse lung tissues. Older mice experienced more severe N protein-induced pneumonia than younger mice. However, treatment with a poly(ADP-ribose) polymerase inhibitor (PJ34) or aromatase inhibitor (anastrozole) relieved N protein-induced pneumonia by restoring Dicer, XPO5, SRSF3, and hnRNPA3 expression. These findings will aid in developing improved treatments for SARS-CoV-2-associated pneumonia.

microbiology↗