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Janies, D. A.

Publications and source records attributed to Janies, D. A..

11 recordsLinked to original sources

Nucleotide-resolution Mapping of RNA N6-Methyladenosine (m6A) modifications and comprehensive analysis of global polyadenylation events in mRNA 3' end processing in malaria pathogen Plasmodium falciparum

Plasmodium falciparum is an obligate human parasite of the phylum Apicomplexa and is the causative agent of the most lethal form of human malaria. Although N6-methyladenosine modification is thought to be one of the major post-transcriptional regulatory mechanisms for stage-specific gene expression in apicomplexan parasites, the precise base position of m6A in mRNAs or noncoding RNAs in these parasites remains unknown. Here, we report global nucleotide-resolution mapping of m6A residues in P. falciparum using DART-seq technology, which quantitatively displayed a stage-specific, dynamic distribution pattern with enrichment near mRNA 3 ends. In this process we identified 894, 788, and 1,762 m6A-modified genes in Ring, Trophozoite and Schizont stages respectively, with an average of 5-7 m6A sites per-transcript at the individual gene level. Notably, several genes involved in malaria pathophysiology, such as KAHRP, ETRAMPs, SERA and stress response genes, such as members of Heat Shock Protein (HSP) family are highly enriched in m6A and therefore could be regulated by this RNA modification. Since we observed preferential methylation at the 3 ends of P. falciparum transcripts and because malaria polyadenylation specificity factor PfCPSF30 harbors an m6A reader YTH domain, we reasoned that m6A might play an important role in 3-end processing of malaria mRNAs. To investigate this, we used two complementary high-throughput RNA 3-end mapping approaches, which provided an initial framework to explore potential roles of m6A in the regulation of alternative polyadenylation (APA) during malaria development in human hosts.

genomics↗

Predicting Antibody and ACE2 Affinity forSARS-CoV-2 BA.2.86 with In Silico ProteinModeling and Docking

The emergence of SARS-CoV-2 lineages derived from Omicron, including BA.2.86 (nicknamed "Pirola") and its relative, JN.1, has raised concerns about their potential impact on public and personal health due to numerous novel mutations. Despite this, predicting their implications based solely on mutation counts proves challenging. Empirical evidence of JN.1s increased immune evasion capacity in relation to previous variants is mixed. To improve predictions beyond what is possible based solely on mutation counts, we conducted extensive in silico analyses on the binding affinity between the RBD of different SARS-CoV-2 variants (Wuhan-Hu-1, BA.1/B.1.1.529, BA.2, XBB.1.5, BA.2.86, and JN.1) and neutralizing antibodies from vaccinated or infected individuals, as well as the human angiotensin-converting enzyme 2 (ACE2) receptor. We observed no statistically significant difference in binding affinity between BA.2.86 or JN.1 and other variants. Therefore, we conclude that the new SARS-CoV-2 variants have no pronounced immune escape or infection capacity compared to previous variants. However, minor reductions in binding affinity for both the antibodies and ACE2 were noted for JN.1. We discuss the implications of the in silico findings and highlight the need for modeling and docking studies to go above and beyond mutation and basic serological neutralization analysis. Future research in this area will benefit from increased structural analyses of memory B-cell derived antibodies and should emphasize the importance of choosing appropriate samples for in silico studies to assess protection provided by vaccination and infection. More-over, the fitness benefits of genomic variation outside of the RBD of BA.2.86 and JN.1 need to be investigated. This research contributes to understanding the BA.2.86 and JN.1 variants potential impact on public health. Taken together, this work introduces a paradigm for functional genomic epidemiology in ongoing efforts to combat the evolving SARS-CoV-2 pandemic and prepare for other hazards.

bioinformatics↗

Positing changes in neutralizing antibody activity for SARS-CoV-2 XBB.1.5 using in silico protein modeling

The SARS-CoV-2 variant XBB.1.5 is of concern as it has high transmissibility. XBB.1.5 currently accounts for upwards of 30% of new infections in the United States. One year after our group published the predicted structure of the Omicron (B.1.1.529) variants receptor binding domain (RBD) and antibody binding affinity, we return to investigate the new mutations seen in XBB.1.5 which is a descendant of Omicron. Using in silico ico modeling approaches against newer neutralizing antibodies that are shown effective against B.1.1.529, we predict the immune consequences of XBB.1.5s mutations and show that there is no statistically significant difference in overall antibody evasion when comparing to the B.1.1.529 and other related variants (e.g., BJ.1 and BM.1.1.1). However, noticeable changes in antibody binding affinity were seen due to specific amino acid changes of interest in the newer variants.

biochemistry↗

EchinoDB: An update to the web-based application for genomic and transcriptomic data on Echinoderms.

Here we release a new version of EchinoDB (https://echinodb.uncc.edu). EchinoDB is a database of genomic and transcriptomic data on echinoderms. The initial database consisted of groups of 749,397 orthologous and paralogous transcripts arranged in orthoclusters by sequence similarity. The new version of EchinoDB includes RNA-seq data of the brittle star Ophioderma brevispinum and high-quality genomic assembly data of the green sea urchin Lytechinus variegatus. In addition, we enabled keyword searches for annotated data and installed an updated version of Sequenceserver to allow BLAST searches. The data are downloadable in FASTA format. The first version of EchinoDB appeared in 2016 and was implemented in GO on a local server. The new version has been updated using R Shiny to include new features and improvements in the application. Furthermore, EchinoDB now runs entirely in the cloud for increased reliability and scaling. EchinoDB enjoys a user base drawn from the fields of phylogenetics, developmental biology, genomics, physiology, neurobiology, and regeneration. As use cases, we illustrate how EchinoDB is used in discovering pathways and gene regulatory networks involved in the tissue regeneration process.

bioinformatics↗

Protein interaction analysis of Plasmodium falciparum circumsporozoite protein variants with human immunoproteins explains RTS,S vaccine efficacy in Ghana

BackgroundThe worlds first malaria vaccine RTS,S provides only partial protection against Plasmodium falciparum infections. The explanation for such low efficacy is unclear. This study examined the associations of parasite genetic variations with binding affinity to human immunological proteins including human leukocyte antigen (HLA) and T cell receptors (TCR) involved in RTS,S-induced immune responses. MethodsMultiplicity of infections was determined by amplicon deep sequencing of merozoite surface protein 1 (PfMSP1). Genetic variations in the C-terminal of circumsporozoite protein (PfMSP1) gene were examined across 88 samples of P. falciparum collected from high and low transmission settings of Ghana. Binding interactions of PfMSP1 variants and HLA/TCR were analyzed using NetChop and HADDOCK predictions. Anti-CSP IgG levels were measured by ELISA in a subset of 10 samples. FindingsHigh polyclonality was detected among P. falciparum infections. A total 27 CSP haplotypes were detected among samples. A significant correlation was detected between the CSP and MSP multiplicity of infection (MOI). No clear clustering of haplotypes was observed by geographic regions. The number of genetic differences in PfCSP between 3D7 and non-3D7 variants does not influence binding interactions to HLA/T cells nor anti-CSP IgG levels. Nevertheless, PfCSP peptide length significantly affects its molecular weight and binding affinity to the HLA. InterpretationsThe presence of multiple non-3D7 strains among P. falciparum infections in Ghana impact the effectiveness of RTS,S. Longer PfCSP peptides may elicit a stronger immune response and should be considered in future version RTS,S. The molecular mechanisms of RTS,S cell-mediated immune responses related to longer CSP peptides warrants further investigations.

bioinformatics↗

Predictions of the SARS-CoV-2 Omicron Variant (B.1.1.529) Spike Protein Receptor-Binding Domain Structure and Neutralizing Antibody Interactions

The genome of the SARS-CoV-2 Omicron variant (B.1.1.529) was released on November 22, 2021, which has caused a flurry of media attention due the large number of mutations it contains. These raw data have spurred questions around vaccine efficacy. Given that neither the structural information nor the experimentally-derived antibody interaction of this variant are available, we have turned to predictive computational methods to model the mutated structure of the spike proteins receptor binding domain and posit potential changes to vaccine efficacy. In this study, we predict some structural changes in the receptor-binding domain that may reduce antibody interaction without completely evading existing neutralizing antibodies (and therefore current vaccines).

molecular biology↗

Heat efficiently inactivates coronaviruses inside vehicles

Heat is an established method to inactivate coronaviruses, and there is utility in using heat to reduce viral load on common touch points in vehicles exposed to a person shedding SARS-CoV-2. As SARS-CoV-2 is a Biosafety level (BSL)-3 pathogen, real world testing of heat as a sanitation method for public and private vehicles becomes a challenge, requiring a surrogate coronavirus that can be handled safely outside of a BSL-3 facility. In this study, we used Bovine Coronavirus (BCoV) as a surrogate for SARS-CoV-2 to test the efficacy of heat-based betacoronavirus inactivation. In vitro, a 30-minute exposure to 56{degrees}C completely inactivated BCoV in solution, and a 15-minute exposure reduced recovery of BCoV >1000-fold. When heated to 56{degrees}C for 15 minutes, the infectivity of BCoV spotted and dried on typical porous and non-porous automobile interior materials was reduced by 99 - 99.99%. When BCoV was spotted and dried on hard plastic (seat) material placed inside an out of service transit bus, 56{degrees}C heat for 30 minutes reduced BCoV infectivity 85 - 99.5%. Thus, 56{degrees}C is an accessible, rapid, and effective method to inactivate coronaviruses inside motor vehicles.

microbiology↗

Ensemble Machine Learning Modeling for the Prediction of Artemisinin Resistance in Malaria

Antiparasitic resistance in malaria is a growing concern affecting many areas of the eastern world. Since the emergence of artemisinin resistance in the late 2000s in Cambodia, research into the underlying mechanisms has been underway. The 2019 Malaria Dream Challenge posited the task of developing computational models that address important problems in advancing the fight against malaria. The first goal was to accurately predict Artemisinin drug resistance levels of Plasmodium falciparum isolates, as quantified by the IC50. The second goal was to predict the parasite clearance rate of malaria parasite isolates based on in vitro transcriptional profiles. In this work, we develop machine learning models using novel methods for transforming isolate data and handling the tens of thousands of variables that result from these data transformation exercises. This is demonstrated by using massively parallel processing of the data vectorization for use in scalable machine learning. In addition, we show the utility of ensemble machine learning modeling for highly effective predictions of both goals of this challenge. This is demonstrated by the use of multiple machine learning algorithms combined with various scaling and normalization preprocessing steps. Then, using a voting ensemble, multiple models are combined to generate a final model prediction.

bioinformatics↗

Enhanced genome annotation strategy provides novel insights on the phylogeny of Flaviviridae

The ongoing and severe public health threat of viruses of the family Flaviviridae, including dengue, hepatitis C, West Nile, yellow fever, and zika, demand a greater understanding of how these viruses evolve, emerge and spread in order to respond. Central to this understanding is an updated phylogeny of the entire family. Unfortunately, most cladograms of Flaviviridae focus on specific lineages, ignore outgroups, and rely on midpoint rooting, hampering their ability to test ingroup monophyly and estimate ingroup relationships. This problem is partly due to the lack of fully annotated genomes of Flaviviridae, which has genera with slightly different gene content, hindering genome analysis without partitioning. To tackle these problems, we developed an annotation pipeline for Flaviviridae that uses a combination of ab initio and homology-based strategies. The pipeline recovered 100% of the genes in reference genomes and annotated over 97% of the expected genes in the remaining non curated sequences. We further demonstrate that the combined analysis of genomes of all genera of Flaviviridae (Flavivirus, Hepacivirus, Pegivirus, and Pestivirus), as made possible by our annotation strategy, enhances the phylogenetic analyses of these viruses for all optimality criteria that we tested (parsimony, maximum likelihood, and posterior probability). The final tree sheds light on the phylogenetic relationship of viruses that are divergent from most Flaviviridae and should be reclassified, especially the soybean cyst nematode virus 5 (SbCNV-5) and the Tamana bat virus. We also corroborate the close phylogenetic relationship of dengue and zika viruses with an unprecedented degree of support.

evolutionary biology↗

Frequent expansion of Plasmodium vivax Duffy Binding Protein in Ethiopia and its epidemiological significance

Plasmodium vivax invasion of human erythrocytes depends on the Duffy Binding Protein (PvDBP) which interacts with the Duffy antigen. PvDBP copy number varies between P. vivax isolates, but the prevalence of PvDBP multiplications in Sub-Saharan Africa and its impact are unknown. We determined the prevalence and type of PvDBP duplications, as well as PvDBP copy number variation among 178 Ethiopian P. vivax isolates using a PCR-based diagnostic method, a novel quantitative real-time PCR assay and whole genome sequencing. For the 145 symptomatic samples, PvDBP duplications were detected in 95 isolates, of which 81 had the Cambodian and 14 Malagasy-type PvDBP duplications. PvDBP varied from 1 to >4 copies. Isolates with multiple PvDBP copies were found to be higher in symptomatic than asymptomatic infections. For the 33 asymptomatic samples, PvDBP was detected with two copies in two of the isolates, and both were the Cambodian-type PvDBP duplication. PvDBP copy number in Duffy-negative heterozygotes was not significantly different from that in Duffy-positives, providing no support for the hypothesis that increased copy number is a specific association with Duffy-negativity, although the number of Duffy-negatives was small and further sampling is required to test this association thoroughly. Author summaryPlasmodium vivax invasion of human erythrocytes relies on interaction between the Duffy antigen and P. vivax Duffy Binding Protein (PvDBP). Whole genome sequences from P. vivax field isolates in Madagascar identified a duplication of the PvDBP gene and PvDBP duplication has also been detected in non-African P. vivax-endemic countries. Two types of PvDBP duplications have been reported, termed Cambodian and Malagasy-type duplications. Our study used a combination of PCR-based diagnostic method, a novel quantitative real-time PCR assay, and whole genome sequencing to determine the prevalence and type of PvDBP duplications, as well as PvDBP copy number on a broad number of P. vivax samples in Ethiopia. We found that over 65% of P. vivax isolated from the symptomatic infections were detected with PvDBP duplications and PvDBP varied from 1 to >4 copies. The majority of PvDBP duplications belongs to the Cambodian-type while the Malagasy-type duplications was also detected. For the asymptomatic infections, despite a small sample size, the majority of P. vivax were detected with a single-copy based on both PCR and qPCR assays. There was no significant difference in PvDBP copy number between Duffy-null heterozygote and Duffy-positive homozygote/heterozygote. Further investigation is needed with expanded Duffy-null homozygotes to examine the functional significance of PvDBP expansion.

epidemiology↗

Tracking a Serial Killer: Integrating Phylogenetic Relationships, Epidemiology, and Geography for Two Invasive Meningococcal Disease Outbreaks

BackgroundWhile overall rates of meningococcal disease have been declining in the United States for the past several decades, New York City (NYC) has experienced two serogroup C meningococcal disease outbreaks in 2005-2006 and in 2010-2013. The outbreaks were centered within drug use and sexual networks, were difficult to control, and required vaccine campaigns.\n\nMethodsWhole Genome Sequencing (WGS) was used to analyze preserved meningococcal isolates collected before and during the two outbreaks. We integrated and analyzed epidemiologic, geographic, and genomic data to better understand transmission networks among patients. Betweenness centrality was used as a metric to understand the most important geographic nodes in the transmission networks. Comparative genomics was used to identify genes associated with the outbreaks.\n\nResultsNeisseria meningitidis serogroup C (ST11/ET-37) was responsible for both outbreaks with each outbreak having distinct phylogenetic clusters. WGS did identify some misclassifications of isolates that were more distant from the rest of the outbreak, as well as those that should have been included based on high genomic similarity. Genomes for the second outbreak were more similar than the first and no mutation was found to either be unique or specific to either outbreak lineage. Betweenness centrality as applied to transmission networks based on phylogenetic analysis demonstrated that the outbreaks were transmitted within focal communities in NYC with few transmission events to other locations.\n\nConclusionsNeisseria meningitidis is an ever changing pathogen and comparative genomic analyses can help elucidate how it spreads geographically to facilitate targeted interventions to interrupt transmission.

genomics↗