Biochemistry Commons^™

Development Of Multivalent Dna-Peptide Nucleosome Mimetics And Multi-Domain Protein Inhibitors That Directly Or Indirectly Target The E3 Ligase Uhrf1, Li Gu

University of the Pacific Theses and Dissertations

UHRF1 is an E3 ubiquitin ligase and a key epigenetic regulator establishing a crosstalk between DNA methylation and histone modification. Despite the important biochemical role of UHRF1 in cells, its overexpression has been found in almost all primary cancer types including breast cancer, lung cancer and so on. Numerous evidence indicates a strong link between tumorigenesis and UHRF1 overexpression, supporting its potential as a universal biomarker for cancer. However, UHRF1 is “yet-to-be drugged” and no highly potent chemical probes have been developed to target UHRF1 to date. In this study, we proposed two drug design approaches for UHRF1. The first …

A Proteomic Analysis To Identify Changes In Bacterial Protein Expression Following Overexpression Of A Spider Silk Protein, Jamie (Ju Yeon) Park, Jaeyoung (Kate) Lee, David Chanyang Eum, Minji Jung, Sungkyung Lee

Pacific Undergraduate Research and Creativity Conference (PURCC)

No abstract provided.

Proteomic Analysis Of The Expression Of Masp1 Dragline Silk Protein In E. Coli, Sophie Rae Pazzo, Rajan Amit Patel, Kamrin Athwal, Edward Kim

Pacific Undergraduate Research and Creativity Conference (PURCC)

No abstract provided.

The Role Of Rad51 In Trichomonas Vaginalis, Dominique Hall

University of the Pacific Theses and Dissertations

Drug resistance to the current treatments on the market is on the rise, therefore there is strong interest in understanding what could be causing the resistance, how resistance could be spreading through the population, and finding some possible new drug targets. One protein of interest is Radiation Sensitive Protein 51 (Rad51). It is a protein that is involved in homologous recombination as well as other processes such as DNA damage repair. While Trichomonas vaginalis traditionally has been known to replicate via binary fission, a modified form of closed mitosis, there is some evidence that meiosis, or at least some form …

Overcoming Obstacles In Protein Expression In The Yeast Pichia Pastoris: Interviews Of Leaders In The Pichia Field, Zoe Ingram, Abha Patkar, Dahoon Oh, Kevin K. Zhang, Christina Chung, Joan Lin-Cereghino, Geoff P. Lin-Cereghino

Pacific Journal of Health

The yeast Pichia pastoris (also known as Komagataella pastoris) has been used for over 30 years to produce thousands of valuable, heterologous proteins, such as insulin to treat diabetes and antibodies to prevent migraine headaches. Despite its success, there are some common, stubborn problems encountered by research scientists when they try to use the yeast to produce their recombinant proteins. In order to provide those working in this field with strategies to overcome these common obstacles, nine experts in P. pastoris protein expression field were interviewed to create a written review and video (https://www.youtube.com/watch?v=FyC9xXVLyD0). This review describes …

Development Of Linked-Domain Protein Inhibitors Of The E2-Conjugating Enzyme Ube2d, Anneroos E. Nederstigt

University of the Pacific Theses and Dissertations

In most eukaryotic organisms, the ubiquitination pathway is one of the most important and versatile signaling systems in use. It is integral to processes such as protein degradation and homeostasis, DNA repair cell cycle regulation, signaling and regulation, epigenetics, and many more. Ubiquitin (Ub) is a short polypeptide of 8.6 kDa, 76 residues that functions as a reversible post-translation modification (PTM). It furthermore contains 7 different lysine residues (K6, K11, K27, K29, K33, K48, K63), all of which can form isopeptide linkages with one another to link individual Ub moieties to form unique polyUb chains onto substrates. The type of …

A Proteomic Analysis Of Corydoras Sterbai Secretions And Tissues, Erik Powell Wictor

University of the Pacific Theses and Dissertations

Defensive mechanisms vary widely in the animal kingdom ranging from physical defenses like spines to chemical defenses such as toxins. Toxins in these secretions and tissues can fluctuate from enzymes to lipids to uncharacterized chemicals. Next generation -omics technology and mass spectrometry are extremely important in analyzing these samples because of their ability to distinguish minute amounts of toxic substance within a complicated sample. The goal of this experiment was to look at secretions and tissues from Corydoras sterbai. All samples in this study were proteolyzed using a mixture of Trypsin and Lys-C, fractionated, and run through nanoLC-MS/MS analysis using …

Proteomic Analysis Of Fetal Rat Neural Stem Cells After Treatment With Hericium Erinaceus, Bright Adam Test

University of the Pacific Theses and Dissertations

The fungus, Hericium erinaceus, has outstanding chemical properties, displaying health benefits in digestive, hepatic, and nervous tissues. Its ease of accessibility and use makes it one of the most common substances used for treatment in Eastern medicine. More and more recent research is confirming the incredible health benefits of this fungus, especially the impact that is seen on nervous tissue growth and recovery post-treatment. Such neurite outgrowth and myelin sheath regeneration could illustrate the beginning of the cure to lifelong neurodegenerative diseases such as Multiple Sclerosis. In this first-of-its-kind study, we cultured and differentiated fetal rat neural stem cells while …

Evaluating Methods Of Obtaining Male Pheromone From Hymenochirus Sp. Using Analytical Chemistry, Vincent Wing-Kun Leung

University of the Pacific Theses and Dissertations

Male Hymenochirus sp. frogs are known to release pheromone that attracts females of the same species. Four methods for collecting secretions containing pheromone in Hymenochirus sp. were tested: norepinephrine injection, gonadotropin-releasing hormone injection, homogenization of gland tissue, and electrostimulation of the skin over the breeding gland area. The samples collected were analyzed using high-performance liquid chromatography (HPLC) and mass spectrometry. The HPLC chromatograph for the male norepinephrine sample contained a peak at 6.4 min that was not in the female norepinephrine sample HPLC chromatograph. The male norepinephrine sample mass spectrum had a peak of m/z 292.0 not in the female …

Structural Characterization Of Black Widow Spider Dragline Silk Proteins Crp1 And Crp4, Mikayla Shanafelt

University of the Pacific Theses and Dissertations

Spider dragline silk is a biomaterial with outstanding material properties, possessing high-tensile strength and toughness. In nature, dragline silk serves a central role during spider locomotion and web construction. Today, scientists are racing to elucidate the molecular machinery governing silk extrusion, attempting to translate this knowledge into a mimicry process in the laboratory to create synthetic fibers for a wide range of different applications. During extrusion, it has been established that biochemical and mechanical forces govern spidroin folding, aggregation, and assembly. In black widow spiders, at least 7 different proteins have been identified as constituents of dragline silk fibers. These …

Knob-Socket Investigation Of Stability And Specificity In Alpha-Helical Secondary And Quaternary Packing Structure, Taylor Renee Rabara

University of the Pacific Theses and Dissertations

The novel knob-socket (KS) model provides a construct to interpret and analyze the direct contributions of amino acid residues to the stability in α-helical protein structures. Based on residue preferences derived from a set of protein structures, the KS construct characterizes intra- and inter-helical packing into regular patterns of simple motifs. The KS model was used in the de novo design of an α-helical homodimer, KSα1.1. Using site-directed mutagenesis, KSα1.1 point mutants were designed to selectively increase and decrease stability by relating KS propensities with changes to α-helical structure. This study suggests that the sockets from the KS Model can …

Creation Of An Immunodeficient Hla-Transgenic Mouse (Humamice) And Functional Validation Of Human Immunity After Transfer Of Hla-Matched Human Cells, Yang Zeng, Bingrun Liu, Marie-Therese Rubio, Xinyue Wang, David M. Ojcius, Ruoping Tang, Antoine Durrbach, Zhitao Ru, Yusen Zhou, Yu-Chun Lone

All Dugoni School of Dentistry Faculty Articles

Research on human immunology has been hindered by the lack of optimal small animal models, given that the protective immune responses of human and non-human species show significant differences. However, due to ethical constraints[1] and the high cost of clinical trials, it is urgent to improve the current animal models that can mimic faithfully human physiology, particularly the human immune system (HIS). HIS mice had been generated recently by engrafting human hematopoietic stem cells (hHSCs) or human peripheral mononuclear cells (hPBMCs) into highly immuno-deficient mice such as NSG, NOG or NRG mice. However, a major experimental drawback for studies using …

Molecular Regulation Of Stem Cell Behavior During Tissue Repair And Cancer Formation, Nestor J. Oviedo

Science Seminar Series

Oviedo will be presenting his work on identifying the mechanisms of adult stem cell fate determination based on their topographical location in the adult body. Understanding stem cell fate determination is crucial because tissue repair and neoplastic growth are greater in anterior than in posterior regions of adult animals. Despite its critical implications for stem cell biology, carcinogenesis and regenerative medicine, this physiological phenomenon has remained overlooked. Recent findings from his group provide intriguing evidence implying DNA repair mechanisms and cellular signaling through post-translational modifications regulate stem cell fate decision depending on their topographical location in the adult body. We …

Isolation, Culture And Characterization Of Hirsutella Sinensis Mycelium From Caterpillar Fungus Fruiting Body, Yun-Fei Komi, Jian-Ching Liau, Chien-Sheng Lee, Chen-Yaw Chiu, Jan Martel, Chuan-Sheng Lin, Shan-Fu Tseng, David M. Ojcius, Chia-Chen Lu, Hsin-Chih Lai, John Ding-E. Young

All Dugoni School of Dentistry Faculty Articles

The caterpillar fungus Ophiocordyceps sinensis (previously called Cordyceps sinensis) has been used for centuries in Asia as a tonic to improve health and longevity. Recent studies show that O. sinensis produces a wide range of biological effects on cells, laboratory animals and humans, including anti-fatigue, anti-infection, anti-inflammatory, antioxidant, and anti-tumor activities. In view of the rarity of O. sinensis fruiting bodies in nature, cultivation of its anamorph mycelium represents a useful alternative for large-scale production. However, O. sinensis fruiting bodies harvested in nature harbor several fungal contaminants, a phenomenon that led to the isolation and characterization of a large number …

Micrornas Modulate Pathogenesis Resulting From Chlamydial Infection In Mice, Laxmi Yeruva, S. Pouncey, Michael R. Eledge, Sudeepa Bhattacharya, Chunqiao Luo, Erin W. Weatherford, David M. Ojcius, Roger G. Rank

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Not all women infected with chlamydiae develop upper genital tract disease, but the reason(s) for this remains undefined. Host genetics and hormonal changes associated with the menstrual cycle are possible explanations for variable infection outcomes. It is also possible that disease severity depends on the virulence of the chlamydial inoculum. It is likely that the inoculum contains multiple genetic variants, differing in virulence. If the virulent variants dominate, then the individual is more likely to develop severe disease. Based on our previous studies, we hypothesized that the relative degree of virulence of a chlamydial population dictates the microRNA (miRNA) expression …

Nucleoside-Diphosphate-Kinase Of P. Gingivalis Is Secreted From Epithelial Cells In The Absence Of A Leader Sequence Through A Pannexin-1 Interactome, Kalina Atanasova, Jungnam Lee, Joann Roberts, Kyulim Lee, David M. Ojcius, Özlem Yilmaz

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Nucleoside-diphosphate-kinases (NDKs) are leaderless, multifunctional enzymes. The mode(s) of NDK secretion is currently undefined, while extracellular translocation of bacterial NDKs is critical for avoidance of host pathogen clearance by opportunistic pathogens such as Porphyromonas gingivalis. P. gingivalis-NDK during infection inhibits extracellular-ATP (eATP)/P2X7-receptor mediated cell death in gingival epithelial cells (GECs) via eATP hydrolysis. Furthermore, depletion of pannexin-1-hemichannel (PNX1) coupled with P2X7-receptor blocks the infection-induced eATP release in GECs, and P. gingivalis-NDK impacts this pathway. Ultrastructural and confocal microscopy of P. gingivalis-co-cultured GECs or green-fluorescent-protein (GFP)-P. gingivalis-NDK transfected GECs revealed a perinuclear/cytoplasmic localization of NDK. eATP stimulation induced NDK recruitment to …

An Iron Detection System Determines Bacterial Swarming Initiation And Biofilm Formation, Chuan-Sheng Lin, Yu-Huan Tsai, Chih-Jung Chang, Shun-Fu Tseng, Tseng-Ru Wu, Chia-Chen Lu, Ting-Shu Wu, Jang-Jih Lu, Jim-Tong Horng, Jan Martel, David M. Ojcius, Hsin-Chih Lai, John Ding-E. Young

All Dugoni School of Dentistry Faculty Articles

Iron availability affects swarming and biofilm formation in various bacterial species. However, how bacteria sense iron and coordinate swarming and biofilm formation remains unclear. Using Serratia marcescens as a model organism, we identify here a stage-specific iron-regulatory machinery comprising a two-component system (TCS) and the TCS-regulated iron chelator 2-isocyano-6,7-dihydroxycoumarin (ICDH-Coumarin) that directly senses and modulates environmental ferric iron (Fe3+) availability to determine swarming initiation and biofilm formation. We demonstrate that the two-component system RssA-RssB (RssAB) directly senses environmental ferric iron (Fe³⁺) and transcriptionally modulates biosynthesis of flagella and the iron chelator ICDH-Coumarin whose production requires the pvc cluster. …

Design Of Novel Ion Channel Modulators, Vladimir Yarov-Yarovoy

Science Seminar Series

Function and modulation of neuronal sodium channels are critical for the neuromodulation of electrical excitability and synaptic transmission in neurons - the basis for many aspects of signal transduction, learning, memory and physiological regulation. Mutations in neuronal voltage-gated sodium channel genes are responsible for various human neurological disorders. Furthermore, human neuronal voltage-gated sodium channels are primary targets of therapeutic drugs used as local anesthetics and for treatment of neurological and cardiac disorders. Yarov-Yarovoy's lab is working on rational design of novel therapeutically useful blockers of voltage-gated sodium channels for treatment of pain and epilepsy. Serious, chronic pain affects at least …

Pyk2 Activates The Nlrp3 Inflammasome By Directly Phosphorylating Asc And Contributes To Inflammasome-Dependent Peritonitis, I-Che Chung, Chun-Nan Ouyang, Sheng-Ning Yuan, Hsin-Pai P. Li, Jeng-Ting Chen, Hui-Ru Shieh, Yu-Jen Chen, David M. Ojcius, Ching-Liang Chu, Jau-Song Yu, Yu-Sun Chang, Lih-Chyang Chen

All Dugoni School of Dentistry Faculty Articles

The inflammasome adaptor protein, ASC, contributes to both innate immune responses and inflammatory diseases via self-oligomerization, which leads to the activation of the protease, caspase-1. Here, we report that the cytosolic tyrosine kinases, FAK and Pyk2, are differentially involved in NLRP3 and AIM2 inflammasome activation. The inhibition of FAK and Pyk2 with RNA interference or chemical inhibitors dramatically abolished ASC oligomerization, caspase-1 activation, and IL-1β secretion in response to NLRP3 or AIM2 stimulation. Pyk2 is phosphorylated by the kinase Syk and relocalizes to the ASC specks upon NLRP3 inflammasome activation. Pyk2, but not FAK, could directly phosphorylate ASC at Tyr146, …

Hepatitis C Virus Frameshift/Alternate Reading Frame Protein Suppresses Interferon Responses Mediated By Pattern Recognition Receptor Retinoic-Acid-Inducible Gene-I, Seung Bum Park, Scott Seronello, Wasima Mayer, David M. Ojcius

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Hepatitis C virus (HCV) actively evades host interferon (IFN) responses but the mechanisms of how it does so are not completely understood. In this study, we present evidence for an HCV factor that contributes to the suppression of retinoic-acid-inducible gene-I (RIG-I)-mediated IFN induction. Expression of frameshift/alternate reading frame protein (F/ARFP) from HCV -2/+1 frame in Huh7 hepatoma cells suppressed type I IFN responses stimulated by HCV RNA pathogen-associated molecular pattern (PAMP) and poly(IC). The suppression occurred independently of other HCV factors; and activation of interferon stimulated genes, TNFα, IFN-λ1, and IFN-λ2/3 was likewise suppressed by HCV F/ARFP. Point mutations in …

Nanoparticle Conversion To Biofilms: In Vitro Demonstration Using Serum-Derived Mineralo-Organic Nanoparticles, Tsui-Yin Wong, Hsin-Hsin Peng, Cheng-Yeu Wu, Jan Martel, David M. Ojcius, Fu-Yung Hsu, John Ding-E. Young

All Dugoni School of Dentistry Faculty Articles

Aims: Mineralo-organic nanoparticles (NPs) detected in biological fluids have been described as precursors of physiological and pathological calcifications in the body. Our main objective was to examine the early stages of mineral NP formation in body fluids. Materials & methods: A nanomaterial approach based on atomic force microscopy, dynamic light scattering, electron microscopy and spectroscopy was used. Results: The mineral particles, which contain the serum proteins albumin and fetuin-A, initially precipitate in the form of round amorphous NPs that gradually grow in size, aggregate and coalesce to form crystalline mineral films similar to the structures observed in calcified human arteries. …

Eosinophils From Murine Lamina Propria Induce Differentiation Of Naïve T Cells Into Regulatory T Cells Via Tgf-Β1 And Retinoic Acid, Hong-Hu Chen, Ai-Hua Sun, David M. Ojcius, Wei-Lin Hu, Yu-Mei Ge, Xu'ai Lin, Lan-Juan Li, Jian-Ping Pan, Jie Yan

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Treg cells play a crucial role in immune tolerance, but mechanisms that induce Treg cells are poorly understood. We here have described eosinophils in lamina propria (LP) that displayed high aldehyde dehydrogenase (ALDH) activity, a rate-limiting step during all-trans retinoic acid (ATRA) synthesis, and expressed TGF-β1 mRNA and high levels of ATRA. Co-incubation assay confirmed that LP eosinophils induced the differentiation of naïve T cells into Treg cells. Differentiation promoted by LP eosinophils were inhibited by blocked either TGF-β1 or ATRA. Peripheral blood (PB) eosinophils did not produce ATRA and could not induce Treg differentiation. These data identifies LP eosinophils …

Detection And Characterization Of Mineralo-Organic Nanoparticles In Human Kidneys, Tsui-Yin Wong, Cheng-Yeu Wu, Jan Martel, Cheng-Wei Lin, Fu-Yung Hsu, David M. Ojcius, Paul Y. Lin, John Ding-E. Young

All Dugoni School of Dentistry Faculty Articles

Ectopic calcification is associated with various human diseases, including atherosclerosis, cancer, chronic kidney disease, and diabetes mellitus. Although mineral nanoparticles have been detected in calcified blood vessels, the nature and role of these particles in the human body remain unclear. Here we show for the first time that human kidney tissues obtained from end-stage chronic kidney disease or renal cancer patients contain round, multilamellar mineral particles of 50 to 1,500 nm, whereas no particles are observed in healthy controls. The mineral particles are found mainly in the extracellular matrix surrounding the convoluted tubules, collecting ducts and loops of Henle as …

Hirsutella Sinensis Mycelium Attenuates Bleomycin-Induced Pulmonary Inflammation And Fibrosis In Vivo, Tsung-Teng Huang, Hsin-Chih Lai, Yun-Fei Ko, David M. Ojcius, Ying-Wei Lan, Jan Martel, John Ding-E. Young, Kowit-Yu Chong

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Hirsutella sinensis mycelium (HSM), the anamorph of Cordyceps sinensis, is a traditional Chinese medicine that has been shown to possess various pharmacological properties. We previously reported that this fungus suppresses interleukin-1β and IL-18 secretion by inhibiting both canonical and non-canonical inflammasomes in human macrophages. However, whether HSM may be used to prevent lung fibrosis and the mechanism underlying this activity remain unclear. Our results show that pretreatment with HSM inhibits TGF-β1–induced expression of fibronectin and α-SMA in lung fibroblasts. HSM also restores superoxide dismutase expression in TGF-β1–treated lung fibroblasts and inhibits reactive oxygen species production in lung epithelial cells. Furthermore, …

Ganoderma Lucidum Reduces Obesity In Mice By Modulating The Composition Of The Gut Microbiota, Chih-Jung Chang, Chuan-Sheng Lin, Chia-Chen Lu, Jan Martel, Yun-Fei Ko, David M. Ojcius, Shun-Fu Tseng, Tsung-Ru Wu, Yi-Yuan Margaret Chen, John Ding-E. Young, Hsin-Chih Lai

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Obesity is associated with low-grade chronic inflammation and intestinal dysbiosis. Ganoderma lucidum is a medicinal mushroom used in traditional Chinese medicine with putative anti-diabetic effects. Here, we show that a water extract of Ganoderma lucidum mycelium (WEGL) reduces body weight, inflammation and insulin resistance in mice fed a high-fat diet (HFD). Our data indicate that WEGL not only reverses HFD-induced gut dysbiosis—as indicated by the decreased Firmicutes-to-Bacteroidetes ratios and endotoxin-bearing Proteobacteria levels—but also maintains intestinal barrier integrity and reduces metabolic endotoxemia. The anti-obesity and microbiota-modulating effects are transmissible via horizontal faeces transfer from WEGL-treated mice to HFD-fed mice. We further …

Aggregatibacter Actinomycetemcomitans Cytolethal Distending Toxin Activates The Nlrp3 Inflammasome In Human Macrophages Leading To The Release Of Pro-Inflammatory Cytokines, Bruce J. Shenker, David M. Ojcius, Lisa P. Walker, Ali Zekavat, Monika Damek Scuron, Kathleen Boesze-Battaglia

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The cytolethal distending toxin (Cdt) is produced from a number of bacteria capable of causing infection and inflammatory disease. Our previous studies with Actinobacillus actinomycetemcomitans Cdt demonstrate not only that the active toxin subunit functions as a phosphatidylinositol-3,4,5-triphosphate (PIP3) phosphatase but also that macrophages exposed to the toxin were stimulated to produce proinflammatory cytokines. We now demonstrate that the Cdt-induced proinflammatory response involves the activation of the NLRP3 inflammasome. Specific inhibitors and short hairpin RNA (shRNA) were employed to demonstrate requirements for NLRP3 and ASC as well as caspase-1. Furthermore, Cdt-mediated inflammasome activation is dependent upon upstream signals, including reactive …

The Pathological Effects Of Ccr2+ Inflammatory Monocytes Are Amplified By An Ifnar1-Triggered Chemokine Feedback Loop In Highly Pathogenic Influenza Infection, Sue-Jane Lin, Ming Lo, Rei-Lin Kuo, Shin-Ru Shih, David M. Ojcius, Jean Lu, Chien-Kuo Lee, Hui-Chen Chen, Meei Yun Lin, Chuen-Miin Leu, Chia-Ni Lin, Ching-Hwa Tsai

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Background: Highly pathogenic influenza viruses cause high levels of morbidity, including excessive infiltration of leukocytes into the lungs, high viral loads and a cytokine storm. However, the details of how these pathological features unfold in severe influenza infections remain unclear. Accumulation of Gr1 + CD11b + myeloid cells has been observed in highly pathogenic influenza infections but it is not clear how and why they accumulate in the severely inflamed lung. In this study, we selected this cell population as a target to investigate the extreme inflammatory response during severe influenza infection.

Results: We established H1N1 IAV-infected mouse models using …

Characterization Of Severe Fever With Thrombocytopenia Syndrome In Rural Regions Of Zhejiang, China, Lei Zhang, Ling Ye, David M. Ojcius, Xiuyu Lou, Chengwei Wang, Cen Feng, Yi Sun, Zhongfa Wang, Shibo Li, Yanjun Zhang

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Severe fever with thrombocytopenia syndrome virus (SFTSV) infections have recently been found in rural regions of Zhejiang. A severe fever with thrombocytopenia syndrome (SFTS) surveillance and sero-epidemiological investigation was conducted in the districts with outbreaks. During the study period of 2011–2014, a total of 51 SFTSV infection cases were identified and the case fatality rate was 12% (6/51). Ninety two percent of the patients (47/51) were over 50 years of age, and 63% (32/51) of laboratory confirmed cases occurred from May to July. Nine percent (11/120) of the serum samples from local healthy people without symptoms were found to be …

A Cytoplasmic Rna Virus Generates Functional Viral Small Rnas And Regulates Viral Ires Activity In Mammalian Cells, Kuo-Feng Weng, Chuan-Tien Hung, Po-Ting Hsieh, Mei-Ling L. Li, Guang-Wu Chen, Yu-An Kung, Peng-Nien Huang, Rei-Lin Kuo, Li-Lien Chen, Jing-Yi Lin, Robert Yung-Liang Wang, Shu-Jen Chen, Petrus Tang, Jim-Tong Horng, Hsing-I Huang, Jen-Ren Wang, David M. Ojcius, Gary Brewer, Shin-Ru Shih

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The roles of virus-derived small RNAs (vsRNAs) have been studied in plants and insects. However, the generation and function of small RNAs from cytoplasmic RNA viruses in mammalian cells remain unexplored. This study describes four vsRNAs that were detected in enterovirus 71-infected cells using next-generation sequencing and northern blots. Viral infection produced substantial levels (>10⁵ copy numbers per cell) of vsRNA1, one of the four vsRNAs. We also demonstrated that Dicer is involved in vsRNA1 generation in infected cells. vsRNA1 overexpression inhibited viral translation and internal ribosomal entry site (IRES) activity in infected cells. Conversely, blocking vsRNA1 enhanced …

The Microtubule-Associated Protein, Eb1, Links Aim2 Inflammasomes With Autophagy-Dependent Secretion, Li-Jie Wang, Hsin-Yi Huang, Meng-Pin Huang, Willisa Liou, Ya-Ting Chang, Chih-Ching Wu, David M. Ojcius, Yu-Sun Chang

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Inflammasomes are multi-protein complexes that regulate chronic inflammation-associated diseases by inducing interleukin-1 β (IL-1β) secretion. Numerous components involved in inflammasome activation have been identified, but the mechanisms of inflammasome-mediated IL-1β secretion have not yet been fully explored. Here, we demonstrate that end-binding protein 1 (EB1), which is required for activation of AIM2 inflammasome complex, links the AIM2 inflammasome to autophagy-dependent secretion. Imaging studies revealed that AIM2 inflammasomes colocalize with microtubule organizing centers and autophagosomes. Biochemical analyses showed that poly(dA-dT)-activated AIM2 inflammasomes induce autophagy and IL-1β secretion in an LC3-dependent fashion. Furthermore, depletion of EB1 decreases autophagic shedding and intracellular trafficking. …