Publications by authors named "Yingfang Liu"

Influenza polymerase (FluPol) carries out both viral transcription and replication using the same viral genome segment as a template to yield distinct end products. However, it remains largely unclear how FluPol synthesizes transcripts containing poly (A) tails during transcription termination, while producing fully complementary products during replication termination. In this study, through structural analysis combined with cell-based and biochemical assays, we identified that the PB1 Leu675/Asn676 and PB2 Arg38 residues of FluPol are critical for transcription termination and polyadenylation.

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Aim: This study employed a three-minute game-based intelligence test (GBIT) to create a hemoglobin polynomial regression model for early identification of mild cognitive impairment (MCI) in older adults.

Methods: 210 older adult participants were recruited from community centers in the central region of Taichung City. Working memory (WM) performance in older adults was assessed during GBIT, while hemoglobin responses were measured by near-infrared spectroscopy (NIRS).

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Sepsis-induced tissue and organ damage is caused by an overactive inflammatory response, immune dysfunction, and coagulation dysfunction. Danger-associated molecular pattern (DAMP) molecules play a critical role in the excessive inflammation observed in sepsis. In our previous research, we identified NMI as a new type of DAMP molecule that promotes inflammation in sepsis by binding to toll-like receptor 4 (TLR4) on macrophage surfaces, activating the NF-κB pathway, and releasing pro-inflammatory cytokines.

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MCM8 and MCM9 form a functional helicase complex (MCM8/9) that plays an essential role in DNA homologous recombination repair for DNA double-strand break. However, the structural characterization of MCM8/9 for DNA binding/unwinding remains unclear. Here, we report structures of the MCM8/9 complex using cryo-electron microscopy single particle analysis.

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Influenza polymerase (FluPol) transcribes viral mRNA at the beginning of the viral life cycle and initiates genome replication after viral protein synthesis. However, it remains poorly understood how FluPol switches between its transcription and replication states, especially given that the structural bases of these two functions are fundamentally different. Here we propose a mechanism by which FluPol achieves functional switching between these two states through a previously unstudied conformation, termed an 'intermediate state'.

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Objective: To evaluate the effectiveness and safety of Xiangsha Liujun pills on the decreased digestive function in patients in the recovery phase of the Coronavirus disease 2019 (COVID-19).

Methods: A randomized, double blind, placebo controlled clinical trial was conducted. A total of 200 COVID-19 patients in the recovery phase were included in our study in Ezhou Hospital of Traditional Chinese Medicine.

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Dengue virus (DENV) is a critical public health concern in tropical and subtropical regions worldwide. Thus, immunocompetent murine models of DENV infection with robust viremia are required for vaccine studies. Diabetes is highly prevalent worldwide, making it frequent comorbidity in patients with dengue fever.

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Acute liver injury caused by overdose usage of acetaminophen (APAP) is an intractable clinical problem. Necrotic hepatocytes release large amounts of intracellular components including damage-associated molecular patterns (DAMPs) which contribute to liver failure and may serve as therapeutic targets. However, the pathogenic mechanisms of DAMPs in APAP-induced liver injury (AILI) are remain largely uncovered.

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The Isw1b chromatin-remodeling complex is specifically recruited to gene bodies to help retain pre-existing histones during transcription by RNA polymerase II. Recruitment is dependent on H3K36 methylation and the Isw1b subunit Ioc4, which contains an N-terminal PWWP domain. Here, we present the crystal structure of the Ioc4-PWWP domain, including a detailed functional characterization of the domain on its own as well as in the context of full-length Ioc4 and the Isw1b remodeler.

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Previous studies have shown that the high mortality caused by viruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza virus primarily results from complications of a cytokine storm. Therefore, it is critical to identify the key factors participating in the cytokine storm. Here we demonstrate that interferon-induced protein 35 (IFP35) plays an important role in the cytokine storm induced by SARS-CoV-2 and influenza virus infection.

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Excessive activation of T cells and microglia represents a hallmark of the pathogenesis of human multiple sclerosis (MS). However, the regulatory molecules overactivating these immune cells remain to be identified. Previously, we reported that extracellular IFP35 family proteins, including IFP35 and NMI, activated macrophages as proinflammatory molecules in the periphery.

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MCM8/9 is a complex involved in homologous recombination (HR) repair pathway. MCM8/9 dysfunction can cause genome instability and result in primary ovarian insufficiency (POI). However, the mechanism underlying these effects is largely unknown.

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DEP domain containing mTOR-interacting protein (DEPTOR) plays pivotal roles in regulating metabolism, growth, autophagy and apoptosis by functions as an endogenous inhibitor of mTOR signaling pathway. Activated by phosphatidic acid, a second messenger in mTOR signaling, DEPTOR dissociates from mTORC1 complex with unknown mechanism. Here, we present a 1.

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Nuclear factor κB (NF-κB)-mediated signaling pathway plays a crucial role in the regulation of inflammatory process, innate and adaptive immune responses. The hyperactivation of inflammatory response causes host cell death, tissue damage, and autoinflammatory disorders, such as sepsis and inflammatory bowel disease. However, how these processes are precisely controlled is still poorly understood.

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Lys deacylases are essential regulators of cell biology in many contexts. Here, we have identified CddA (cyanobacterial deacetylase/depropionylase), a Lys deacylase enzyme expressed in the cyanobacterium sp. PCC 7002 that has both deacetylase and depropionylase activity.

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Autophagy is a conserved process that delivers cytosolic substances to the lysosome for degradation, but its direct role in the regulation of antiviral innate immunity remains poorly understood. Here, through high-throughput screening, we discovered that CCDC50 functions as a previously unknown autophagy receptor that negatively regulates the type I interferon (IFN) signaling pathway initiated by RIG-I-like receptors (RLRs), the sensors for RNA viruses. The expression of CCDC50 is enhanced by viral infection, and CCDC50 specifically recognizes K63-polyubiquitinated RLRs, thus delivering the activated RIG-I/MDA5 for autophagic degradation.

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Minichromosome maintenance 8 (MCM8) is a recently identified member of the minichromosome maintenance family, which possesses helicase and ATPase activity. It interacts with MCM9 and participates in homologous recombination repair. The structure of MCM8 is unclear now.

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Chromosome translocation is a major cause of the onset and progression of diverse types of cancers. However, the mechanisms underlying this process remain poorly understood. Here, we identified a non-homologous end-joining protein, IFFO1, which structurally forms a heterotetramer with XRCC4.

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AlpK is an essential monooxygenase involved in the biosynthesis of kinamycin. It catalyzes the C5-hyfroxylattion of the crucial benzo[b]-fluorence intermediate in kinamycin synthesis. However, the structure and mechanism of AlpK is unclear.

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Endosomal transport represents the primary mode for intracellular trafficking and signaling transduction and thus has to be tightly controlled. The molecular processes controlling the endosomal positioning utilize several large protein complexes, one of which contains the small GTPase Rab7, Rab-interacting lysosomal protein (RILP), and oxysterol-binding protein-related protein 1 (ORP1L). Rab7 is known to interact with RILP through a canonical binding site termed the effector-interacting switch region, but it is not clear how Rab7 interacts with ORP1L, limiting our understanding of the overall process.

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NS1-binding protein (NS1-BP), which belongs to the Kelch protein superfamily, was first identified as a novel human 70 kDa protein that interacts with NS1 of Influenza A virus. It is involved in many cell functions, including pre-mRNA splicing, the ERK signalling pathway, the aryl hydrocarbon receptor (AHR) pathway, F-actin organization and protein ubiquitylation. However, the structure of NS1-BP is still unknown, which may impede functional studies.

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Protein-disulfide isomerase-like protein of the testis (PDILT), a member of the protein-disulfide isomerase family, is a chaperone essential for the folding of spermatogenesis-specific proteins in male postmeiotic germ cells. However, the structural mechanisms that regulate the chaperone function of PDILTs are unknown. Here, we report the structures of human PDILT (hPDILT) determined by X-ray crystallography to 2.

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Damage-associated molecular patterns (DAMP) trigger innate immune response and exacerbate inflammation to combat infection and cellular damage. Identifying DAMPs and revealing their functions are thus of crucial importance. Here we report that two molecules, N-myc and STAT interactor (NMI) and interferon-induced protein 35 (IFP35) act as DAMPs and are released by activated macrophages during lipopolysaccharide-induced septic shock or acetaminophen-induced liver injury.

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Purpose: Our aim was to characterize the newly established new drug conditional approval process in China and discuss the challenges and opportunities with respect to new drug research and development and registration.

Methods: We examined the new approval program through literature review, law analysis, and data analysis. Data were derived from published materials, such as journal articles, government publications, press releases, and news articles, along with statistical data from INSIGHT-China Pharma Databases, the China Food and Drug Administration website, the Center for Drug Evaluation website, the US Food and Drug Administration website, and search results published by Google.

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