Identification of Cellular Factors Required for SARS-CoV-2 Replication

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the recently emerged virus responsible for the COVID-19 pandemic. Clinical presentation can range from asymptomatic disease and mild respiratory tract infection to severe disease with lung injury, multiorgan failure, and death. SARS-CoV-2 is the third animal coronavirus to emerge in humans in the 21st century, and coronaviruses appear to possess a unique ability to cross borders between species and infect a wide range of organisms. This is somewhat surprising as, except for the requirement of host cell receptors, cell–pathogen interactions are usually species-specific. Insights into these host–virus interactions will provide a deeper understanding of the process of SARS-CoV-2 infection and provide a means for the design and development of antiviral agents. In this study, we describe a complex analysis of SARS-CoV-2 infection using a genome-wide CRISPR-Cas9 knock-out system in HeLa cells overexpressing entry receptor angiotensin-converting enzyme 2 (ACE2). This platform allows for the identification of factors required for viral replication. This study was designed to include a high number of replicates (48 replicates; 16 biological repeats with 3 technical replicates each) to prevent data instability, remove sources of bias, and allow multifactorial bioinformatic analyses in order to study the resulting interaction network. The results obtained provide an interesting insight into the replication mechanisms of SARS-CoV-2.

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NTPase/helicase of Flaviviridae: inhibitors and inhibition of the enzyme.

Acta Biochimica Polonica ◽

10.18388/abp.2002_3769 ◽

2002 ◽

Vol 49 (3) ◽

pp. 597-614 ◽

Cited By ~ 20

Author(s):

Peter Borowski ◽

Andreas Niebuhr ◽

Herbert Schmitz ◽

Ramachandra S Hosmane ◽

Maria Bretner ◽

...

Keyword(s):

Antiviral Agents ◽

Large Family ◽

Enzymatic Activities ◽

Structural Protein ◽

Knock Out ◽

Antiviral Therapies ◽

Wide Range ◽

Development And Differentiation ◽

Transcription And Replication

RNA nucleoside triphosphatases (NTPase)/helicases represent a large family of proteins that are ubiquitously distributed over a wide range of organisms. The enzymes play essential role in cell development and differentiation, and some of them are involved in transcription and replication of viral single-stranded RNA genomes. The enzymatic activities of a NTPase/helicase were also detected in the carboxyl-terminal non-structural protein 3 (NS3) of members of the Flaviviridae family. The crucial role of the enzyme for the virus life cycle was demonstrated in knock out experiments and by using NTPase/helicase specific inhibitors. This makes the enzyme an attractive target for development of Flaviviridae-specific antiviral therapies. This review will summarize our knowledge about the function and structure of the enzyme, update the spectrum of inhibitors of the enzymatic activities of the NTPase/helicase and describe the different mechanisms by which the compounds act. Some of the compounds reviewed herein could show potential utility as antiviral agents against Flaviviridae viruses.

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A Novel Bioinformatics Method for Efficient Knowledge Discovery by BLSOM from Big Genomic Sequence Data

BioMed Research International ◽

10.1155/2014/765648 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11

Author(s):

Yu Bai ◽

Yuki Iwasaki ◽

Shigehiko Kanaya ◽

Yue Zhao ◽

Toshimichi Ikemura

Keyword(s):

Genomic Sequence ◽

Sequence Data ◽

Self Organizing Map ◽

Genome Signature ◽

A Genome ◽

Wide Range ◽

Oligonucleotide Composition ◽

Species Specific

With remarkable increase of genomic sequence data of a wide range of species, novel tools are needed for comprehensive analyses of the big sequence data. Self-Organizing Map (SOM) is an effective tool for clustering and visualizing high-dimensional data such as oligonucleotide composition on one map. By modifying the conventional SOM, we have previously developed Batch-Learning SOM (BLSOM), which allows classification of sequence fragments according to species, solely depending on the oligonucleotide composition. In the present study, we introduce the oligonucleotide BLSOM used for characterization of vertebrate genome sequences. We first analyzed pentanucleotide compositions in 100 kb sequences derived from a wide range of vertebrate genomes and then the compositions in the human and mouse genomes in order to investigate an efficient method for detecting differences between the closely related genomes. BLSOM can recognize the species-specific key combination of oligonucleotide frequencies in each genome, which is called a “genome signature,” and the specific regions specifically enriched in transcription-factor-binding sequences. Because the classification and visualization power is very high, BLSOM is an efficient powerful tool for extracting a wide range of information from massive amounts of genomic sequences (i.e., big sequence data).

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Introns structure patterns of variation in nucleotide composition in Arabidopsis thaliana and rice protein-coding genes

10.1101/010819 ◽

2014 ◽

Author(s):

Adrienne Ressayre ◽

Sylvain Glemin ◽

Pierre Montalent ◽

Laurana Serres-Giardi ◽

Christine Dillmann ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Nucleotide Composition ◽

Coding Region ◽

Protein Coding ◽

Plant Genomes ◽

A Genome ◽

Wide Range ◽

Intron Number ◽

Species Specific ◽

Range Of Variation

Plant genomes are large, intron-rich and present a wide range of variation in coding region G+C content. Concerning coding regions, a sort of syndrome can be described in plants: the increase in G+C content is associated with both the increase in heterogeneity among genes within a genome and the increase in variation across genes. Taking advantage of the large number of genes composing plant genomes and the wide range of variation in gene intron number, we performed a comprehensive survey of the patterns of variation in G+C content at different scales from the nucleotide level to the genome scale in two species Arabidopsis thaliana and Oryza sativa, comparing the patterns in genes with different intron numbers. In both species, we observed a pervasive effect of gene intron number and location along genes on G+C content, codon and amino acid frequencies suggesting that in both species, introns have a barrier effect structuring G+C content along genes. In external gene regions (located upstream first or downstream last intron), species-specific factors are shaping G+C content while in internal gene regions (surrounded by introns), G+C content is constrained to remain within a range common to both species. In rice, introns appear as a major determinant of gene G+C content while in A. thaliana introns have a weaker but significant effect. The structuring effect of introns in both species is susceptible to explain the G+C content syndrome observed in plants.

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Multiple Myeloma or Brucellosis: A Case Report

Infectious Disorders - Drug Targets ◽

10.2174/1871526519666190307123047 ◽

2020 ◽

Vol 20 (1) ◽

pp. 102-105 ◽

Cited By ~ 1

Author(s):

Hossein A. Rahdar ◽

Mansoor Kodori ◽

Mohamad R. Salehi ◽

Mahsa Doomanlou ◽

Morteza Karami-Zarandi ◽

...

Keyword(s):

Multiple Myeloma ◽

Brucella Melitensis ◽

Severe Disease ◽

Correct Diagnosis ◽

Clinical Manifestations ◽

Bone Marrow Aspiration ◽

Major Health Problem ◽

Brucella Infection ◽

Wide Range ◽

Parental Treatment

Background: Brucellosis, a major health problem in developing countries, is a multisystem infection with a broad spectrum of clinical manifestations. Hematological complications, ranging from an intravascular coagulopathy to mild homeostasis disorders (such as gammopathy), have been reported in brucella infection. These signs and symptoms may lead to misdiagnosis of brucellosis with other hematological diseases. Case: A 65-year-old male whose occupation was shepherding was referred to our hospital as a known case of multiple myeloma with continuous fever, muscle weakness, and night sweating after taking 2 courses of chemotherapy. The laboratory diagnosis of multiple myeloma had been based on the observation of a high percent of plasma cells in the bone marrow aspiration. At follow- up, the result of patient's fever workup, with 2 sets of blood cultures, was positive for Brucella melitensis. Isolated brucella was confirmed as B. melitensis by 16S rRNA sequencing. Brucellosis serologic test was performed by agglutination test and positive results were obtained. The patient was discharged with the cessation of fever and general improvement after the end of the parental treatment phase of brucella bacteremia. Conclusions: Brucella infection may cause a severe disease, mimicking a primary hematological disease, which could complicate the correct diagnosis. In brucellosis cases, due to the wide range of symptoms, in addition to cultivation and serological methods, molecular methods should also be used to prevent inappropriate diagnosis and additional costs.

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Human Coronaviruses: Counteracting the Damage by Storm

Viruses ◽

10.3390/v13081457 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1457

Author(s):

Dewald Schoeman ◽

Burtram C. Fielding

Keyword(s):

Immune Response ◽

Severe Disease ◽

Antiviral Agents ◽

The Elderly ◽

Highly Pathogenic ◽

Vaccine Responses ◽

Cell Mediated Immune Response ◽

Inhibition Antibody ◽

A Cell ◽

Human Coronaviruses

Over the past 18 years, three highly pathogenic human (h) coronaviruses (CoVs) have caused severe outbreaks, the most recent causative agent, SARS-CoV-2, being the first to cause a pandemic. Although much progress has been made since the COVID-19 pandemic started, much about SARS-CoV-2 and its disease, COVID-19, is still poorly understood. The highly pathogenic hCoVs differ in some respects, but also share some similarities in clinical presentation, the risk factors associated with severe disease, and the characteristic immunopathology associated with the progression to severe disease. This review aims to highlight these overlapping aspects of the highly pathogenic hCoVs—SARS-CoV, MERS-CoV, and SARS-CoV-2—briefly discussing the importance of an appropriately regulated immune response; how the immune response to these highly pathogenic hCoVs might be dysregulated through interferon (IFN) inhibition, antibody-dependent enhancement (ADE), and long non-coding RNA (lncRNA); and how these could link to the ensuing cytokine storm. The treatment approaches to highly pathogenic hCoV infections are discussed and it is suggested that a greater focus be placed on T-cell vaccines that elicit a cell-mediated immune response, using rapamycin as a potential agent to improve vaccine responses in the elderly and obese, and the potential of stapled peptides as antiviral agents.

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Genetic, lifestyle, and health-related characteristics of adults without celiac disease who follow a gluten-free diet: a population-based study of 124,447 participants

American Journal of Clinical Nutrition ◽

10.1093/ajcn/nqaa291 ◽

2020 ◽

Author(s):

Thomas J Littlejohns ◽

Amanda Y Chong ◽

Naomi E Allen ◽

Matthew Arnold ◽

Kathryn E Bradbury ◽

...

Keyword(s):

Celiac Disease ◽

Genome Wide Association Study ◽

Population Based ◽

Gluten Free Diet ◽

Hospital Inpatient ◽

Gluten Free ◽

A Genome ◽

Wide Range ◽

Health Related ◽

Reported Health

ABSTRACT Background The number of gluten-free diet followers without celiac disease (CD) is increasing. However, little is known about the characteristics of these individuals. Objectives We address this issue by investigating a wide range of genetic and phenotypic characteristics in association with following a gluten-free diet. Methods The cross-sectional association between lifestyle and health-related characteristics and following a gluten-free diet was investigated in 124,447 women and men aged 40–69 y from the population-based UK Biobank study. A genome-wide association study (GWAS) of following a gluten-free diet was performed. Results A total of 1776 (1.4%) participants reported following a gluten-free diet. Gluten-free diet followers were more likely to be women, nonwhite, highly educated, living in more socioeconomically deprived areas, former smokers, have lost weight in the past year, have poorer self-reported health, and have made dietary changes as a result of illness. Conversely, these individuals were less likely to consume alcohol daily, be overweight or obese, have hypertension, or use cholesterol-lowering medication. Participants with hospital inpatient diagnosed blood and immune mechanism disorders (OR: 1.62; 95% CI: 1.18, 2.21) and non-CD digestive system diseases (OR: 1.58; 95% CI: 1.42, 1.77) were more likely to follow a gluten-free diet. The GWAS demonstrated that no genetic variants were associated with being a gluten-free diet follower. Conclusions Gluten-free diet followers have a better cardiovascular risk profile than non-gluten-free diet followers but poorer self-reported health and a higher prevalence of blood and immune disorders and digestive conditions. Reasons for following a gluten-free diet warrant further investigation.

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Informing the public health response to COVID-19: a systematic review of risk factors for disease, severity, and mortality

BMC Infectious Diseases ◽

10.1186/s12879-021-05992-1 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

M. Flook ◽

C. Jackson ◽

E. Vasileiou ◽

C. R. Simpson ◽

M. D. Muckian ◽

...

Keyword(s):

Public Health ◽

Risk Factors ◽

Systematic Review ◽

At Risk ◽

Risk Factor ◽

Disease Severity ◽

Severe Disease ◽

Public Health Response ◽

Wide Range ◽

Multivariable Analyses

Abstract Background Severe Acute Respiratory Syndrome coronavirus-2 (SARS-CoV-2) has challenged public health agencies globally. In order to effectively target government responses, it is critical to identify the individuals most at risk of coronavirus disease-19 (COVID-19), developing severe clinical signs, and mortality. We undertook a systematic review of the literature to present the current status of scientific knowledge in these areas and describe the need for unified global approaches, moving forwards, as well as lessons learnt for future pandemics. Methods Medline, Embase and Global Health were searched to the end of April 2020, as well as the Web of Science. Search terms were specific to the SARS-CoV-2 virus and COVID-19. Comparative studies of risk factors from any setting, population group and in any language were included. Titles, abstracts and full texts were screened by two reviewers and extracted in duplicate into a standardised form. Data were extracted on risk factors for COVID-19 disease, severe disease, or death and were narratively and descriptively synthesised. Results One thousand two hundred and thirty-eight papers were identified post-deduplication. Thirty-three met our inclusion criteria, of which 26 were from China. Six assessed the risk of contracting the disease, 20 the risk of having severe disease and ten the risk of dying. Age, gender and co-morbidities were commonly assessed as risk factors. The weight of evidence showed increasing age to be associated with severe disease and mortality, and general comorbidities with mortality. Only seven studies presented multivariable analyses and power was generally limited. A wide range of definitions were used for disease severity. Conclusions The volume of literature generated in the short time since the appearance of SARS-CoV-2 has been considerable. Many studies have sought to document the risk factors for COVID-19 disease, disease severity and mortality; age was the only risk factor based on robust studies and with a consistent body of evidence. Mechanistic studies are required to understand why age is such an important risk factor. At the start of pandemics, large, standardised, studies that use multivariable analyses are urgently needed so that the populations most at risk can be rapidly protected. Registration This review was registered on PROSPERO as CRD42020177714.

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A genome-scale metabolic model of Saccharomyces cerevisiae that integrates expression constraints and reaction thermodynamics

Nature Communications ◽

10.1038/s41467-021-25158-6 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Omid Oftadeh ◽

Pierre Salvy ◽

Maria Masid ◽

Maxime Curvat ◽

Ljubisa Miskovic ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Expression System ◽

Biomass Composition ◽

Industrial Biotechnology ◽

Overflow Metabolism ◽

Cellular Expression ◽

A Genome ◽

Wide Range ◽

Eukaryotic Organisms ◽

Genome Scale

AbstractEukaryotic organisms play an important role in industrial biotechnology, from the production of fuels and commodity chemicals to therapeutic proteins. To optimize these industrial systems, a mathematical approach can be used to integrate the description of multiple biological networks into a single model for cell analysis and engineering. One of the most accurate models of biological systems include Expression and Thermodynamics FLux (ETFL), which efficiently integrates RNA and protein synthesis with traditional genome-scale metabolic models. However, ETFL is so far only applicable for E. coli. To adapt this model for Saccharomyces cerevisiae, we developed yETFL, in which we augmented the original formulation with additional considerations for biomass composition, the compartmentalized cellular expression system, and the energetic costs of biological processes. We demonstrated the ability of yETFL to predict maximum growth rate, essential genes, and the phenotype of overflow metabolism. We envision that the presented formulation can be extended to a wide range of eukaryotic organisms to the benefit of academic and industrial research.

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Determinants of vitamin D status in Kenyan calves

Scientific Reports ◽

10.1038/s41598-020-77209-5 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Rebecca Callaby ◽

Emma Hurst ◽

Ian Handel ◽

Phil Toye ◽

Barend M. de C. Bronsvoort ◽

...

Keyword(s):

Infectious Disease ◽

Vitamin D ◽

Health Outcomes ◽

Critical Role ◽

Subsequent Development ◽

Vitamin D Metabolites ◽

Vitamin D Status ◽

Skeletal Health ◽

A Genome ◽

Wide Range

AbstractVitamin D plays a critical role in calcium homeostasis and in the maintenance and development of skeletal health. Vitamin D status has increasingly been linked to non-skeletal health outcomes such as all-cause mortality, infectious diseases and reproductive outcomes in both humans and veterinary species. We have previously demonstrated a relationship between vitamin D status, assessed by the measurement of serum concentrations of the major vitamin D metabolite 25 hydroxyvitamin D (25(OH)D), and a wide range of non-skeletal health outcomes in companion and wild animals. The aims of this study were to define the host and environmental factors associated with vitamin D status in a cohort of 527 calves from Western Kenya which were part of the Infectious Disease of East African Livestock (IDEAL) cohort. A secondary aim was to explore the relationship between serum 25(OH)D concentrations measured in 7-day old calves and subsequent health outcomes over the following 12 months. A genome wide association study demonstrated that both dietary and endogenously produced vitamin D metabolites were under polygenic control in African calves. In addition, we found that neonatal vitamin D status was not predictive of the subsequent development of an infectious disease event or mortality over the 12 month follow up period.

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Genome-wide mapping of unexplored essential regions in the Saccharomyces cerevisiae genome: evidence for hidden synthetic lethal combinations in a genetic interaction network

Nucleic Acids Research ◽

10.1093/nar/gku576 ◽

2014 ◽

Vol 42 (15) ◽

pp. 9838-9853 ◽

Cited By ~ 6

Author(s):

Saeed Kaboli ◽

Takuya Yamakawa ◽

Keisuke Sunada ◽

Tao Takagaki ◽

Yu Sasano ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Genetic Interaction ◽

Interaction Network ◽

Essential Genes ◽

Genetic Interactions ◽

Lethal Gene ◽

Synthetic Lethal ◽

Genome Wide ◽

A Genome ◽

Wide Scale

Abstract Despite systematic approaches to mapping networks of genetic interactions in Saccharomyces cerevisiae, exploration of genetic interactions on a genome-wide scale has been limited. The S. cerevisiae haploid genome has 110 regions that are longer than 10 kb but harbor only non-essential genes. Here, we attempted to delete these regions by PCR-mediated chromosomal deletion technology (PCD), which enables chromosomal segments to be deleted by a one-step transformation. Thirty-three of the 110 regions could be deleted, but the remaining 77 regions could not. To determine whether the 77 undeletable regions are essential, we successfully converted 67 of them to mini-chromosomes marked with URA3 using PCR-mediated chromosome splitting technology and conducted a mitotic loss assay of the mini-chromosomes. Fifty-six of the 67 regions were found to be essential for cell growth, and 49 of these carried co-lethal gene pair(s) that were not previously been detected by synthetic genetic array analysis. This result implies that regions harboring only non-essential genes contain unidentified synthetic lethal combinations at an unexpectedly high frequency, revealing a novel landscape of genetic interactions in the S. cerevisiae genome. Furthermore, this study indicates that segmental deletion might be exploited for not only revealing genome function but also breeding stress-tolerant strains.

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