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Glutathione S-Transferase Regulates Mitochondrial Populations In Axons Through Increased Glutathione Oxidation, Gaynor A. Smith, Tzu-Huai Lin, Amy E. Sheehan, Wynand Van Der Goes Van Naters, Lukas J. Neukomm, Hillary K. Graves, Dana M. Bis-Brewer, Stephan Zuchner, Marc R. Freeman Jul 2019

Glutathione S-Transferase Regulates Mitochondrial Populations In Axons Through Increased Glutathione Oxidation, Gaynor A. Smith, Tzu-Huai Lin, Amy E. Sheehan, Wynand Van Der Goes Van Naters, Lukas J. Neukomm, Hillary K. Graves, Dana M. Bis-Brewer, Stephan Zuchner, Marc R. Freeman

Open Access Articles

Mitochondria are essential in long axons to provide metabolic support and sustain neuron integrity. A healthy mitochondrial pool is maintained by biogenesis, transport, mitophagy, fission, and fusion, but how these events are regulated in axons is not well defined. Here, we show that the Drosophila glutathione S-transferase (GST) Gfzf prevents mitochondrial hyperfusion in axons. Gfzf loss altered redox balance between glutathione (GSH) and oxidized glutathione (GSSG) and initiated mitochondrial fusion through the coordinated action of Mfn and Opa1. Gfzf functioned epistatically with the thioredoxin peroxidase Jafrac1 and the thioredoxin reductase 1 TrxR-1 to regulate mitochondrial dynamics. Altering GSH:GSSG ratios ...


Control Of Antiviral Innate Immune Response By Protein Geranylgeranylation, Shigao Yang, Zhaozhao Jiang, Katherine A. Fitzgerald, Donghai Wang May 2019

Control Of Antiviral Innate Immune Response By Protein Geranylgeranylation, Shigao Yang, Zhaozhao Jiang, Katherine A. Fitzgerald, Donghai Wang

Open Access Articles

The mitochondrial antiviral signaling protein (MAVS) orchestrates host antiviral innate immune response to RNA virus infection. However, how MAVS signaling is controlled to eradicate virus while preventing self-destructive inflammation remains obscure. Here, we show that protein geranylgeranylation, a posttranslational lipid modification of proteins, limits MAVS-mediated immune signaling by targeting Rho family small guanosine triphosphatase Rac1 into the mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs) at the mitochondria-ER junction. Protein geranylgeranylation and subsequent palmitoylation promote Rac1 translocation into MAMs upon viral infection. MAM-localized Rac1 limits MAVS' interaction with E3 ligase Trim31 and hence inhibits MAVS ubiquitination, aggregation, and activation. Rac1 also facilitates ...


Adipocyte Acly Facilitates Dietary Carbohydrate Handling To Maintain Metabolic Homeostasis In Females, Sully Fernandez, John M. Viola, Annmarie Torres, Martina Wallace, Sophie Trefely, Steven Zhao, Hayley C. Affronti, Jivani M. Gengatharan, David A. Guertin, Nathaniel W. Snyder, Christian M. Metallo, Kathryn E. Wellen May 2019

Adipocyte Acly Facilitates Dietary Carbohydrate Handling To Maintain Metabolic Homeostasis In Females, Sully Fernandez, John M. Viola, Annmarie Torres, Martina Wallace, Sophie Trefely, Steven Zhao, Hayley C. Affronti, Jivani M. Gengatharan, David A. Guertin, Nathaniel W. Snyder, Christian M. Metallo, Kathryn E. Wellen

Open Access Articles

Sugars and refined carbohydrates are major components of the modern diet. ATP-citrate lyase (ACLY) is upregulated in adipocytes in response to carbohydrate consumption and generates acetyl-coenzyme A (CoA) for both lipid synthesis and acetylation reactions. Here, we investigate the role of ACLY in the metabolic and transcriptional responses to carbohydrates in adipocytes and unexpectedly uncover a sexually dimorphic function in maintaining systemic metabolic homeostasis. When fed a high-sucrose diet, Acly(FAT-/-) females exhibit a lipodystrophy-like phenotype, with minimal fat accumulation, insulin resistance, and hepatic lipid accumulation, whereas Acly(FAT-/-) males have only mild metabolic phenotypes. We find that ACLY is ...


An Order-To-Disorder Structural Switch Activates The Foxm1 Transcription Factor, Aimee H. Marceau, Caileen M. Brison, Santrupti Nerli, Heather E. Arsenault, Andrew C. Mcshan, Eefei Chen, Hsiau-Wei Lee, Jennifer A. Benanti, Nikolaos G. Sgourakis, Seth M. Rubin May 2019

An Order-To-Disorder Structural Switch Activates The Foxm1 Transcription Factor, Aimee H. Marceau, Caileen M. Brison, Santrupti Nerli, Heather E. Arsenault, Andrew C. Mcshan, Eefei Chen, Hsiau-Wei Lee, Jennifer A. Benanti, Nikolaos G. Sgourakis, Seth M. Rubin

Open Access Articles

Intrinsically disordered transcription factor transactivation domains (TADs) function through structural plasticity, adopting ordered conformations when bound to transcriptional co-regulators. Many transcription factors contain a negative regulatory domain (NRD) that suppresses recruitment of transcriptional machinery through autoregulation of the TAD. We report the solution structure of an autoinhibited NRD-TAD complex within FoxM1, a critical activator of mitotic gene expression. We observe that while both the FoxM1 NRD and TAD are primarily intrinsically disordered domains, they associate and adopt a structured conformation. We identify how Plk1 and Cdk kinases cooperate to phosphorylate FoxM1, which releases the TAD into a disordered conformation that ...


Serum Deprivation Of Mesenchymal Stem Cells Improves Exosome Activity And Alters Lipid And Protein Composition, Reka A. Haraszti, Rachael Miller, Michelle L. Dubuke, Andrew H. Coles, Marie C. Didiot, Dimas Echeverria, Matteo Stoppato, Yves Y. Sere, John D. Leszyk, Julia F. Alterman, Bruno M. D. C. Godinho, Matthew R. Hassler, Rachel Wollacott, Yan Wang, Scott A. Shaffer, Neil Aronin, Anastasia Khvorova May 2019

Serum Deprivation Of Mesenchymal Stem Cells Improves Exosome Activity And Alters Lipid And Protein Composition, Reka A. Haraszti, Rachael Miller, Michelle L. Dubuke, Andrew H. Coles, Marie C. Didiot, Dimas Echeverria, Matteo Stoppato, Yves Y. Sere, John D. Leszyk, Julia F. Alterman, Bruno M. D. C. Godinho, Matthew R. Hassler, Rachel Wollacott, Yan Wang, Scott A. Shaffer, Neil Aronin, Anastasia Khvorova

Open Access Articles

Exosomes can serve as delivery vehicles for advanced therapeutics. The components necessary and sufficient to support exosomal delivery have not been established. Here we connect biochemical composition and activity of exosomes to optimize exosome-mediated delivery of small interfering RNAs (siRNAs). This information is used to create effective artificial exosomes. We show that serum-deprived mesenchymal stem cells produce exosomes up to 22-fold more effective at delivering siRNAs to neurons than exosomes derived from control cells. Proteinase treatment of exosomes stops siRNA transfer, indicating that surface proteins on exosomes are involved in trafficking. Proteomic and lipidomic analyses show that exosomes derived in ...


Cognitive And Microbiome Impacts Of Experimental Ancylostoma Ceylanicum Hookworm Infections In Hamsters, Samuel C. Pan, Doyle V. Ward, Yunqiang Yin, Yan Hu, Elfawal A. Mostafa, Robert E. Clark, Raffi V. Aroian May 2019

Cognitive And Microbiome Impacts Of Experimental Ancylostoma Ceylanicum Hookworm Infections In Hamsters, Samuel C. Pan, Doyle V. Ward, Yunqiang Yin, Yan Hu, Elfawal A. Mostafa, Robert E. Clark, Raffi V. Aroian

Open Access Articles

Hookworms are one of the most prevalent and important parasites, infecting ~500 million people worldwide. Hookworm disease is among the leading causes of iron-deficiency anemia in the developing world and is associated with significant growth stunting and malnutrition. In humans, hookworms appear to impair memory and other forms of cognition, although definitive data are hard to come by. Here we study the impact of a human hookworm parasite, Ancylostoma ceylanicum, on cognition in hamsters in a controlled laboratory setting. We developed tests that measure long-term memory in hamsters. We find that hookworm-infected hamsters were fully capable of detecting a novel ...


Dysfunction In Serotonergic And Noradrenergic Systems And Somatic Symptoms In Psychiatric Disorders, Yi Liu, Jingping Zhao, Xiaoduo Fan, Wenbin Guo May 2019

Dysfunction In Serotonergic And Noradrenergic Systems And Somatic Symptoms In Psychiatric Disorders, Yi Liu, Jingping Zhao, Xiaoduo Fan, Wenbin Guo

Open Access Articles

Somatic symptoms include a range of physical experiences, such as pain, muscle tension, body shaking, difficulty in breathing, heart palpitation, blushing, fatigue, and sweating. Somatic symptoms are common in major depressive disorder (MDD), anxiety disorders, and some other psychiatric disorders. However, the etiology of somatic symptoms remains unclear. Somatic symptoms could be a response to emotional distress in patients with those psychiatric conditions. Increasing evidence supports the role of aberrant serotoninergic and noradrenergic neurotransmission in somatic symptoms. The physiological alterations underlying diminished serotonin (5-HT) and norepinephrine (NE) signaling may contribute to impaired signal transduction, reduced 5-HT, or NE release from ...


Plasma Indoleamine 2,3-Dioxygenase Activity As A Potential Biomarker For Early Diagnosis Of Multidrug-Resistant Tuberculosis In Tuberculosis Patients, Wen Shi, Juan Wu, Qi Tan, Chun-Mei Hu, Xia Zhang, Hong-Qiu Pan, Zhen Yang, Meng-Yu He, Min Yu, Bo Zhang, Wei-Ping Xie, Hong Wang May 2019

Plasma Indoleamine 2,3-Dioxygenase Activity As A Potential Biomarker For Early Diagnosis Of Multidrug-Resistant Tuberculosis In Tuberculosis Patients, Wen Shi, Juan Wu, Qi Tan, Chun-Mei Hu, Xia Zhang, Hong-Qiu Pan, Zhen Yang, Meng-Yu He, Min Yu, Bo Zhang, Wei-Ping Xie, Hong Wang

Open Access Articles

Purpose: Multidrug-resistant tuberculosis (MDR-TB) remains a challenge of global TB control, with difficulty in early detection of drug-sensitive tuberculosis (DS-TB). We investigate the diagnostic significance of IDO as a potential biomarker to discriminate MDR patients among the TB patients.

Patients and methods: Plasma indoleamine 2,3-dioxygenase (IDO) was measured by the ratio of kynurenine (Kyn) to tryptophan (Trp) concentrations, using high performance liquid chromatography-mass spectrometry (LC-MS/MS). Chest computed tomography (CT) imaging signs from TB patients were collected and analyzed in 18 DS-TB patients, 16 MDR-TB patients, 6 lung cancer (LC) patients, and 11 healthy individuals. Lung imaging signs from ...


Jnk(1/2) Represses Lkb(1)-Deficiency-Induced Lung Squamous Cell Carcinoma Progression, Jian Liu, Tianyuan Wang, Chad J. Creighton, San-Pin Wu, Madhumita Ray, Kyathanahalli S. Janardhan, Cynthia J. Willson, Sung-Nam Cho, Patricia D. Castro, Michael M. Ittmann, Jian-Liang Li, Roger J. Davis, Francesco J. Demayo May 2019

Jnk(1/2) Represses Lkb(1)-Deficiency-Induced Lung Squamous Cell Carcinoma Progression, Jian Liu, Tianyuan Wang, Chad J. Creighton, San-Pin Wu, Madhumita Ray, Kyathanahalli S. Janardhan, Cynthia J. Willson, Sung-Nam Cho, Patricia D. Castro, Michael M. Ittmann, Jian-Liang Li, Roger J. Davis, Francesco J. Demayo

Open Access Articles

Mechanisms of lung squamous cell carcinoma (LSCC) development are poorly understood. Here, we report that JNK1/2 activities attenuate Lkb1-deficiency-driven LSCC initiation and progression through repressing DeltaNp63 signaling. In vivo Lkb1 ablation alone is sufficient to induce LSCC development by reducing MKK7 levels and JNK1/2 activities, independent of the AMPKalpha and mTOR pathways. JNK1/2 activities is positively regulated by MKK7 during LSCC development. Pharmaceutically elevated JNK1/2 activities abates Lkb1 dependent LSCC formation while compound mutations of Jnk1/2 and Lkb1 further accelerate LSCC progression. JNK1/2 is inactivated in a substantial proportion of human LSCC and JNK1 ...


Gwas For Quantitative Resistance Phenotypes In Mycobacterium Tuberculosis Reveals Resistance Genes And Regulatory Regions, Maha R. Farhat, Luca Freschi, Roger Calderon, Thomas Ioerger, Matthew Snyder, Conor J. Meehan, Bouke De Jong, Leen Rigouts, Alexander Sloutsky, Devinder Kaur, Shamil Sunyaev, Dick Van Soolingen, Jay Shendure, Jim Sacchettini, Megan Murray May 2019

Gwas For Quantitative Resistance Phenotypes In Mycobacterium Tuberculosis Reveals Resistance Genes And Regulatory Regions, Maha R. Farhat, Luca Freschi, Roger Calderon, Thomas Ioerger, Matthew Snyder, Conor J. Meehan, Bouke De Jong, Leen Rigouts, Alexander Sloutsky, Devinder Kaur, Shamil Sunyaev, Dick Van Soolingen, Jay Shendure, Jim Sacchettini, Megan Murray

Open Access Articles

Drug resistance diagnostics that rely on the detection of resistance-related mutations could expedite patient care and TB eradication. We perform minimum inhibitory concentration testing for 12 anti-TB drugs together with Illumina whole-genome sequencing on 1452 clinical Mycobacterium tuberculosis (MTB) isolates. We evaluate genome-wide associations between mutations in MTB genes or non-coding regions and resistance, followed by validation in an independent data set of 792 patient isolates. We confirm associations at 13 non-canonical loci, with two involving non-coding regions. Promoter mutations are measured to have smaller average effects on resistance than gene body mutations. We estimate the heritability of the resistance ...


Circulating Micrornas Mir-331 And Mir-195 Differentiate Local Luminal A From Metastatic Breast Cancer, Peter Mcanena, Kahraman Tanriverdi, Catherine Curran, K. Gilligan, Jane E. Freedman, James A. L. Brown, Michael J. Kerin May 2019

Circulating Micrornas Mir-331 And Mir-195 Differentiate Local Luminal A From Metastatic Breast Cancer, Peter Mcanena, Kahraman Tanriverdi, Catherine Curran, K. Gilligan, Jane E. Freedman, James A. L. Brown, Michael J. Kerin

Open Access Articles

BACKGROUND: Breast cancer is the leading cause of cancer related death in women, with metastasis the principle cause of mortality. New non-invasive prognostic markers are needed for the early detection of metastasis, facilitating treatment decision optimisation. MicroRNA (miRNA) are small, non-coding RNAs regulating gene expression and involved in many cellular processes, including metastasis. As biomarkers, circulating miRNAs (in blood) hold great promise for informing diagnosis or monitoring treatment responses.

METHODS: Plasma extracted RNA from age matched local Luminal A (n = 4) or metastatic disease (n = 4) were profiled using Next Generation Sequencing. Selected differentially expressed miRNA were validated on a ...


Alzheimer's Disease Microbiome Is Associated With Dysregulation Of The Anti-Inflammatory P-Glycoprotein Pathway, John P. Haran, Shakti K. Bhattarai, Sage Foley, Protiva Dutta, Doyle V. Ward, Vanni Bucci, Beth A. Mccormick May 2019

Alzheimer's Disease Microbiome Is Associated With Dysregulation Of The Anti-Inflammatory P-Glycoprotein Pathway, John P. Haran, Shakti K. Bhattarai, Sage Foley, Protiva Dutta, Doyle V. Ward, Vanni Bucci, Beth A. Mccormick

Open Access Articles

The microbiota-gut-brain axis is a bidirectional communication system that is poorly understood. Alzheimer's disease (AD), the most common cause of dementia, has long been associated with bacterial infections and inflammation-causing immunosenescence. Recent studies examining the intestinal microbiota of AD patients revealed that their microbiome differs from that of subjects without dementia. In this work, we prospectively enrolled 108 nursing home elders and followed each for up to 5 months, collecting longitudinal stool samples from which we performed metagenomic sequencing and in vitro T84 intestinal epithelial cell functional assays for P-glycoprotein (P-gp) expression, a critical mediator of intestinal homeostasis. Our ...


Enhanced Cas12a Editing In Mammalian Cells And Zebrafish, Pengpeng Liu, Kevin Luk, Masahiro Shin, Feston Idrizi, Samantha F. Kwok, Benjamin P. Roscoe, Esther Mintzer, Sneha Suresh, Kyle Morrison, Josias B. Frazao, Mehmet Fatih Bolukbasi, Karthikeyan Ponnienselvan, Jeremy Luban, Lihua Julie Zhu, Nathan D. Lawson, Scot A. Wolfe May 2019

Enhanced Cas12a Editing In Mammalian Cells And Zebrafish, Pengpeng Liu, Kevin Luk, Masahiro Shin, Feston Idrizi, Samantha F. Kwok, Benjamin P. Roscoe, Esther Mintzer, Sneha Suresh, Kyle Morrison, Josias B. Frazao, Mehmet Fatih Bolukbasi, Karthikeyan Ponnienselvan, Jeremy Luban, Lihua Julie Zhu, Nathan D. Lawson, Scot A. Wolfe

Open Access Articles

Type V CRISPR-Cas12a systems provide an alternate nuclease platform to Cas9, with potential advantages for specific genome editing applications. Here we describe improvements to the Cas12a system that facilitate efficient targeted mutagenesis in mammalian cells and zebrafish embryos. We show that engineered variants of Cas12a with two different nuclear localization sequences (NLS) on the C terminus provide increased editing efficiency in mammalian cells. Additionally, we find that pre-crRNAs comprising a full-length direct repeat (full-DR-crRNA) sequence with specific stem-loop G-C base substitutions exhibit increased editing efficiencies compared with the standard mature crRNA framework. Finally, we demonstrate in zebrafish embryos that the ...


Brown Fat Organogenesis And Maintenance Requires Akt1 And Akt2, Joan Sanchez-Gurmaches, Camila Martinez Calejman, Su Myung Jung, Huawei Li, David A. Guertin May 2019

Brown Fat Organogenesis And Maintenance Requires Akt1 And Akt2, Joan Sanchez-Gurmaches, Camila Martinez Calejman, Su Myung Jung, Huawei Li, David A. Guertin

Open Access Articles

OBJECTIVE: Understanding the signaling mechanisms that control brown adipose tissue (BAT) development is relevant to understanding energy homeostasis and obesity. The AKT kinases are insulin effectors with critical in vivo functions in adipocytes; however, their role in adipocyte development remains poorly understood. The goal of this study was to investigate AKT function in BAT development.

METHODS: We conditionally deleted Akt1 and Akt2 either individually or together with Myf5-Cre, which targets early mesenchymal precursors that give rise to brown adipocytes. Because Myf5-Cre also targets skeletal muscle and some white adipocyte lineages, comparisons were made between AKT function in BAT versus white ...


Iiv-6 Inhibits Nf-Kappab Responses In Drosophila, Cara C. West, Florentina Rus, Ying Chen, Anni Kleino, Monique Gangloff, Don B. Gammon, Neal S. Silverman May 2019

Iiv-6 Inhibits Nf-Kappab Responses In Drosophila, Cara C. West, Florentina Rus, Ying Chen, Anni Kleino, Monique Gangloff, Don B. Gammon, Neal S. Silverman

Open Access Articles

The host immune response and virus-encoded immune evasion proteins pose constant, mutual selective pressure on each other. Virally encoded immune evasion proteins also indicate which host pathways must be inhibited to allow for viral replication. Here, we show that IIV-6 is capable of inhibiting the two Drosophila NF-kappaB signaling pathways, Imd and Toll. Antimicrobial peptide (AMP) gene induction downstream of either pathway is suppressed when cells infected with IIV-6 are also stimulated with Toll or Imd ligands. We find that cleavage of both Imd and Relish, as well as Relish nuclear translocation, three key points in Imd signal transduction, occur ...


Regulation Of The Drosophila Imd Pathway By Signaling Amyloids, Anni Kleino, Neal S. Silverman May 2019

Regulation Of The Drosophila Imd Pathway By Signaling Amyloids, Anni Kleino, Neal S. Silverman

Open Access Articles

Fruit flies elicit effective defense responses against numerous microbes. The responses against Gram-negative bacteria are mediated by the Imd pathway, an evolutionarily conserved NF-kappaB pathway recognizing meso-diaminopimelic acid (DAP)-type peptidoglycan from bacterial cell walls. Several reviews already provide a detailed view of ligand recognition and signal transduction during Imd signaling, but the formation and regulation of the signaling complex immediately downstream of the peptidoglycan-sensing receptors is still elusive. In this review, we focus on the formation of the Imd amyloidal signaling center and post-translational modifications in the assembly and disassembly of the Imd signaling complex.


Ouabain Enhances Cell-Cell Adhesion Mediated By Beta1 Subunits Of The Na(+),K(+)-Atpase In Cho Fibroblasts, Claudia Andrea Vilchis-Nestor, Maria Luisa Roldan, Angelina Leonardi, Juan G. Navea, Teresita Padilla-Benavides, Liora Shoshani Apr 2019

Ouabain Enhances Cell-Cell Adhesion Mediated By Beta1 Subunits Of The Na(+),K(+)-Atpase In Cho Fibroblasts, Claudia Andrea Vilchis-Nestor, Maria Luisa Roldan, Angelina Leonardi, Juan G. Navea, Teresita Padilla-Benavides, Liora Shoshani

Open Access Articles

Adhesion is a crucial characteristic of epithelial cells to form barriers to pathogens and toxic substances from the environment. Epithelial cells attach to each other using intercellular junctions on the lateral membrane, including tight and adherent junctions, as well as the Na(+),K(+)-ATPase. Our group has shown that non-adherent chinese hamster ovary (CHO) cells transfected with the canine beta1 subunit become adhesive, and those homotypic interactions amongst beta1 subunits of the Na(+),K(+)-ATPase occur between neighboring epithelial cells. Ouabain, a cardiotonic steroid, binds to the alpha subunit of the Na(+),K(+)-ATPase, inhibits the pump activity and induces ...


Exercise Rescues Gene Pathways Involved In Vascular Expansion And Promotes Functional Angiogenesis In Subcutaneous White Adipose Tissue, So Yun Min, Heather Learnard, Shashi Kant, Olga Gaelikman, Raziel Rojas-Rodriguez, Tiffany Desouza, Anand Desai, John F. Keaney Jr., Silvia Corvera, Siobhan M. Craige Apr 2019

Exercise Rescues Gene Pathways Involved In Vascular Expansion And Promotes Functional Angiogenesis In Subcutaneous White Adipose Tissue, So Yun Min, Heather Learnard, Shashi Kant, Olga Gaelikman, Raziel Rojas-Rodriguez, Tiffany Desouza, Anand Desai, John F. Keaney Jr., Silvia Corvera, Siobhan M. Craige

Open Access Articles

Exercise mitigates chronic diseases such as diabetes, cardiovascular diseases, and obesity; however, the molecular mechanisms governing protection from these diseases are not completely understood. Here we demonstrate that exercise rescues metabolically compromised high fat diet (HFD) fed mice, and reprograms subcutaneous white adipose tissue (scWAT). Using transcriptomic profiling, scWAT was analyzed for HFD gene expression changes that were rescued by exercise. Gene networks involved in vascularization were identified as prominent targets of exercise, which led us to investigate the vasculature architecture and endothelial phenotype. Vascular density in scWAT was found to be compromised in HFD, and exercise rescued this defect ...


Exploiting Unique Biological Features Of Leukemia Stem Cells For Therapeutic Benefit, Haojian Zhang, Shaoguang Li Apr 2019

Exploiting Unique Biological Features Of Leukemia Stem Cells For Therapeutic Benefit, Haojian Zhang, Shaoguang Li

Open Access Articles

Cancer stem cells play a critical role in disease initiation and insensitivity to chemotherapy in numerous hematologic malignancies and some solid tumors, and these stem cells need to be eradicated to achieve a cure. Key to successful targeting of cancer stem cells is to identify and functionally test critical target genes and to fully understand their associated molecular network in these stem cells. Human chronic myeloid leukemia (CML) is well accepted as one of the typical types of hematopoietic malignancies that are derived from leukemia stem cells (LSCs), serving as an excellent model disease for understanding the biology of LSCs ...


A Highly Expressed Intestinal Cysteine Protease Of Ancylostoma Ceylanicum Protects Vaccinated Hamsters From Hookworm Infection, Jason B. Noon, Erich M. Schwarz, Gary R. Ostroff, Raffi V. Aroian Apr 2019

A Highly Expressed Intestinal Cysteine Protease Of Ancylostoma Ceylanicum Protects Vaccinated Hamsters From Hookworm Infection, Jason B. Noon, Erich M. Schwarz, Gary R. Ostroff, Raffi V. Aroian

Open Access Articles

BACKGROUND: Human hookworms (Necator americanus, Ancylostoma duodenale, and Ancylostoma ceylanicum) are intestinal blood-feeding parasites that infect ~500 million people worldwide and are among the leading causes of iron-deficiency anemia in the developing world. Drugs are useful against hookworm infections, but hookworms rapidly reinfect people, and the parasites can develop drug resistance. Therefore, having a hookworm vaccine would be of tremendous benefit.

METHODOLOGY/PRINCIPAL FINDINGS: We investigated the vaccine efficacy in outbred Syrian hamsters of three A. ceylanicum hookworm antigen candidates from two classes of proteins previously identified as promising vaccine candidates. These include two intestinally-enriched, putatively secreted cathepsin B cysteine ...


Single-Cell Rna-Sequencing-Based Crispri Screening Resolves Molecular Drivers Of Early Human Endoderm Development, Ryan M. Genga, Eric M. Kernfeld, Krishna M. Parsi, Teagan J. Parsons, Michael J. Ziller, Rene Maehr Apr 2019

Single-Cell Rna-Sequencing-Based Crispri Screening Resolves Molecular Drivers Of Early Human Endoderm Development, Ryan M. Genga, Eric M. Kernfeld, Krishna M. Parsi, Teagan J. Parsons, Michael J. Ziller, Rene Maehr

Open Access Articles

Studies in vertebrates have outlined conserved molecular control of definitive endoderm (END) development. However, recent work also shows that key molecular aspects of human END regulation differ even from rodents. Differentiation of human embryonic stem cells (ESCs) to END offers a tractable system to study the molecular basis of normal and defective human-specific END development. Here, we interrogated dynamics in chromatin accessibility during differentiation of ESCs to END, predicting DNA-binding proteins that may drive this cell fate transition. We then combined single-cell RNA-seq with parallel CRISPR perturbations to comprehensively define the loss-of-function phenotype of those factors in END development. Following ...


The Nua4 Acetyltransferase And Histone H4 Acetylation Promote Replication Recovery After Topoisomerase I-Poisoning, Chiaki Noguchi, Tanu Singh, Melissa A. Ziegler, Jasmine D. Peake, Lyne Khair, Ana Aza, Toru M. Nakamura, Eishi Noguchi Apr 2019

The Nua4 Acetyltransferase And Histone H4 Acetylation Promote Replication Recovery After Topoisomerase I-Poisoning, Chiaki Noguchi, Tanu Singh, Melissa A. Ziegler, Jasmine D. Peake, Lyne Khair, Ana Aza, Toru M. Nakamura, Eishi Noguchi

Open Access Articles

BACKGROUND: Histone acetylation plays an important role in DNA replication and repair because replicating chromatin is subject to dynamic changes in its structures. However, its precise mechanism remains elusive. In this report, we describe roles of the NuA4 acetyltransferase and histone H4 acetylation in replication fork protection in the fission yeast Schizosaccharomyces pombe.

RESULTS: Downregulation of NuA4 subunits renders cells highly sensitive to camptothecin, a compound that induces replication fork breakage. Defects in NuA4 function or mutations in histone H4 acetylation sites lead to impaired recovery of collapsed replication forks and elevated levels of Rad52 DNA repair foci, indicating the ...


The Role Of Platelets In Mediating A Response To Human Influenza Infection, Milka Koupenova-Zamor, Heather A. Corkrey, Olga Vitseva, Giorgia Manni, Catherine J. Pang, Lauren Clancy, Chen Yao, Jeffrey J. Rade, Daniel Levy, Jennifer P. Wang, Robert W. Finberg, Evelyn A. Kurt-Jones, Jane E. Freedman Apr 2019

The Role Of Platelets In Mediating A Response To Human Influenza Infection, Milka Koupenova-Zamor, Heather A. Corkrey, Olga Vitseva, Giorgia Manni, Catherine J. Pang, Lauren Clancy, Chen Yao, Jeffrey J. Rade, Daniel Levy, Jennifer P. Wang, Robert W. Finberg, Evelyn A. Kurt-Jones, Jane E. Freedman

Open Access Articles

Influenza infection increases the incidence of myocardial infarction but the reason is unknown. Platelets mediate vascular occlusion through thrombotic functions but are also recognized to have immunomodulatory activity. To determine if platelet processes are activated during influenza infection, we collected blood from 18 patients with acute influenza infection. Microscopy reveals activated platelets, many containing viral particles and extracellular-DNA associated with platelets. To understand the mechanism, we isolate human platelets and treat them with influenza A virus. Viral-engulfment leads to C3 release from platelets as a function of TLR7 and C3 leads to neutrophil-DNA release and aggregation. TLR7 specificity is confirmed ...


The Erk Mapk Pathway Is Essential For Skeletal Development And Homeostasis, Jung-Min Kim, Yeon-Suk Yang, Kwang Hwan Park, Hwanhee Oh, Matthew B. Greenblatt, Jae-Hyuck Shim Apr 2019

The Erk Mapk Pathway Is Essential For Skeletal Development And Homeostasis, Jung-Min Kim, Yeon-Suk Yang, Kwang Hwan Park, Hwanhee Oh, Matthew B. Greenblatt, Jae-Hyuck Shim

Open Access Articles

Mitogen-activated protein kinases (MAPKs) are a family of protein kinases that function as key signal transducers of a wide spectrum of extracellular stimuli, including growth factors and pro-inflammatory cytokines. Dysregulation of the extracellular signal-regulated kinase (ERK) MAPK pathway is associated with human skeletal abnormalities including Noonan syndrome, neurofibromatosis type 1, and cardiofaciocutaneous syndrome. Here, we demonstrate that ERK activation in osteoprogenitors is required for bone formation during skeletal development and homeostasis. Deletion of Mek1 and Mek2, kinases upstream of ERK MAPK, in osteoprogenitors (Mek1(Osx)Mek2(-/-)), resulted in severe osteopenia and cleidocranial dysplasia (CCD), similar to that seen in humans ...


Genome-Scale Crispr Screens Identify Human Pluripotency-Specific Genes, Robert J. Ihry, Zinger Yang, Ajamete Kaykas Apr 2019

Genome-Scale Crispr Screens Identify Human Pluripotency-Specific Genes, Robert J. Ihry, Zinger Yang, Ajamete Kaykas

Open Access Articles

Human pluripotent stem cells (hPSCs) generate a variety of disease-relevant cells that can be used to improve the translation of preclinical research. Despite the potential of hPSCs, their use for genetic screening has been limited by technical challenges. We developed a scalable and renewable Cas9 and sgRNA-hPSC library in which loss-of-function mutations can be induced at will. Our inducible mutant hPSC library can be used for multiple genome-wide CRISPR screens in a variety of hPSC-induced cell types. As proof of concept, we performed three screens for regulators of properties fundamental to hPSCs: their ability to self-renew and/or survive (fitness ...


The Er-Localized Protein Dfcp1 Modulates Er-Lipid Droplet Contact Formation, Dongfang Li, Yan G. Zhao, Di Li, Hongyu Zhao, Jie Huang, Guangyan Miao, Du Feng, Pingsheng Liu, Dong Li, Hong Zhang Apr 2019

The Er-Localized Protein Dfcp1 Modulates Er-Lipid Droplet Contact Formation, Dongfang Li, Yan G. Zhao, Di Li, Hongyu Zhao, Jie Huang, Guangyan Miao, Du Feng, Pingsheng Liu, Dong Li, Hong Zhang

Open Access Articles

Very little is known about the spatiotemporal generation of lipid droplets (LDs) from the endoplasmic reticulum (ER) and the factors that mediate ER-LD contacts for LD growth. Using super-resolution grazing incidence structured illumination microscopy (GI-SIM) live-cell imaging, we reveal that upon LD induction, the ER-localized protein DFCP1 redistributes to nascent puncta on the ER, whose formation depends on triglyceride synthesis. These structures move along the ER and fuse to form expanding LDs. Fusion and expansion of DFCP1-labeled nascent structures is controlled by BSCL2. BSCL2 depletion causes accumulation of nascent DFCP1 structures. DFCP1 overexpression increases LD size and enhances ER-LD contacts ...


Transient Kinetic Analysis Of Swr1c-Catalyzed H2a.Z Deposition Unravels The Impact Of Nucleosome Dynamics And The Asymmetry Of Histone Exchange, Raushan K. Singh, Jiayi Fan, Nathan Gioacchini, Shinya Watanabe, Osman Bilsel, Craig L. Peterson Apr 2019

Transient Kinetic Analysis Of Swr1c-Catalyzed H2a.Z Deposition Unravels The Impact Of Nucleosome Dynamics And The Asymmetry Of Histone Exchange, Raushan K. Singh, Jiayi Fan, Nathan Gioacchini, Shinya Watanabe, Osman Bilsel, Craig L. Peterson

Open Access Articles

The SWR1C chromatin remodeling enzyme catalyzes ATP-dependent replacement of nucleosomal H2A with the H2A.Z variant, regulating key DNA-mediated processes such as transcription and DNA repair. Here, we investigate the transient kinetic mechanism of the histone exchange reaction, employing ensemble FRET, fluorescence correlation spectroscopy (FCS), and the steady-state kinetics of ATP hydrolysis. Our studies indicate that SWR1C modulates nucleosome dynamics on both the millisecond and microsecond timescales, poising the nucleosome for the dimer exchange reaction. The transient kinetic analysis of the remodeling reaction performed under single turnover conditions unraveled a striking asymmetry in the ATP-dependent replacement of nucleosomal dimers, promoted ...


Structural But Not Functional Alterations In Cones In The Absence Of The Retinal Disease Protein Retinitis Pigmentosa 2 (Rp2) In A Cone-Only Retina, Linjing Li, Kollu N. Rao, Hemant Khanna Apr 2019

Structural But Not Functional Alterations In Cones In The Absence Of The Retinal Disease Protein Retinitis Pigmentosa 2 (Rp2) In A Cone-Only Retina, Linjing Li, Kollu N. Rao, Hemant Khanna

Open Access Articles

X-linked retinitis pigmentosa 2 (XLRP2) patients and Rp2 (null) mice exhibit severe cone photoreceptor degeneration. However, due to the paucity of cones in mammalian model systems, it is not clear how cones respond to the loss of RP2. Here we have used the Nrl(-/-) mice, which develop a rodless and short wavelength (S) opsin-containing cone-only retina, to generate Rp2 (null)::Nrl(-/-) double knock out (Rp2-DKO) mice. We found that the ciliary axoneme and the outer segments (OSs) of the cones were significantly longer with disorganized membrane infoldings as compared to the Nrl(-/-) mice. Additionally, we found misregulation in the expression ...


Two Unique Cases Of X-Linked Scid: A Diagnostic Challenge In The Era Of Newborn Screening, Pooja Purswani, Anne Marie Comeau, Jaime E. Hale, Jolan E. Walter Apr 2019

Two Unique Cases Of X-Linked Scid: A Diagnostic Challenge In The Era Of Newborn Screening, Pooja Purswani, Anne Marie Comeau, Jaime E. Hale, Jolan E. Walter

Open Access Articles

In the era of newborn screening (NBS) for severe combined immunodeficiency (SCID) and the possibility of gene therapy (GT), it is important to link SCID phenotype to the underlying genetic disease. In western countries, X-linked interleukin 2 receptor gamma chain (IL2RG) and adenosine deaminase (ADA) deficiency SCID are two of the most common types of SCID and can be treated by GT. As a challenge, both IL2RG and ADA genes are highly polymorphic and a gene-based diagnosis may be difficult if the variant is of unknown significance or if it is located in non-coding areas of the genes that are ...


Or14i1 Is A Receptor For The Human Cytomegalovirus Pentameric Complex And Defines Viral Epithelial Cell Tropism, Xiaofei E, Paul Meraner, Ping Lu, Jill M. Perreira, Aaron M. Aker, William M. Mcdougall, Ronghua Zhuge, Gary C. Chan, Rachel M. Gerstein, Patrizia Caposio, Andrew D. Yurochko, Abraham L. Brass, Timothy F. Kowalik Apr 2019

Or14i1 Is A Receptor For The Human Cytomegalovirus Pentameric Complex And Defines Viral Epithelial Cell Tropism, Xiaofei E, Paul Meraner, Ping Lu, Jill M. Perreira, Aaron M. Aker, William M. Mcdougall, Ronghua Zhuge, Gary C. Chan, Rachel M. Gerstein, Patrizia Caposio, Andrew D. Yurochko, Abraham L. Brass, Timothy F. Kowalik

Open Access Articles

A human cytomegalovirus (HCMV) pentameric glycoprotein complex (PC), gH-gL-UL128-UL130-UL131A, is necessary for viral infection of clinically relevant cell types, including epithelial cells, which are important for interhost transmission and disease. We performed genome-wide CRISPR/Cas9 screens of different cell types in parallel to identify host genes specifically required for HCMV infection of epithelial cells. This effort identified a multipass membrane protein, OR14I1, as a receptor for HCMV infection. This olfactory receptor family member is required for HCMV attachment, entry, and infection of epithelial cells and is dependent on the presence of viral PC. OR14I1 is required for AKT activation and ...