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Kumar, M.

Publications and source records attributed to Kumar, M..

At least 73 records · Page 4Linked to original sources

VIRAL METAGENOMIC SURVEY OF CASPIAN SEALS

Viral diseases of pinnipeds cause substantial mortality and morbidity and can influence population demography. Viral metagenomic studies can therefore play an important role in pinniped health assessments and disease surveillance relevant to both individual species and in a One Health context. This study used a metagenomic approach with high throughput sequencing to make the first assessment of viral diversity in Caspian seals (Pusa caspica), the only marine mammal species endemic to the Caspian Sea. Sequencing libraries from 35 seals sampled 2009-2020 were analysed, finding sequences from the viral families Picornaviridae, Adenoviridae, Circoviridae, Herpesviridae, Papillomaviridae, Caliciviridae, Orthomyxoviridae, Anelloviridae, Smacoviridae, Cruciviridae and Parvoviridae. The similarity of viral contigs from Caspian seal to sequences to those recovered from other pinnipeds ranged from 63.74% (San Miguel sea lion calicivirus) to 78.79% (Seal anellovirus 4). Some may represent novel viral species, but overall, the viral repertoire of Caspian seals is similar to available viromes from other pinnipeds. Among the sequences recovered were partial contigs for influenza B, representing only the second such molecular identification in marine mammals. This work provides a foundation for further studies of viral communities in Caspian seals, the diversity of viromes in pinnipeds more generally, and contributes data relevant for disease risk assessments in marine mammals.

microbiology↗

Assessing the impact of autologous neutralizing antibodies on rebound dynamics in postnatally SHIV-infected ART-treated infant Rhesus macaques

AO_SCPLOWBSTRACTC_SCPLOWThe presence of antibodies against HIV in infected children is associated with a greater capacity to control viremia in the absence of therapy. While the benefits of early antiretroviral treatment (ART) in infants are well documented, early ART may interfere with the development of antibody responses. In contrast to adults, early treated children lack detectable HIV-specific antibodies, suggesting a fundamental difference in HIV pathogenesis. Despite this potential adverse effect, early ART may decrease the size of the latent reservoir established early in infection in infants, which can be beneficial in viral control. Understanding the virologic and immunologic aspects of pediatric HIV is crucial to inform innovative targeted strategies for treating children living with HIV. In this study, we investigate how ART initiation time sets the stage for trade-offs in the latent reservoir establishment and the development of humoral immunity and how these, in turn, affect post-treatment dynamics. We also elucidate the biological function of antibodies in pediatric HIV. We employ mathematical modeling coupled with experimental data from an infant nonhuman primate Simian/Human Immunodeficiency Virus (SHIV) infection model. Infant Rhesus macaques (RMs) were orally challenged with SHIV.C.CH505 375H dCT four weeks after birth and started treatment at different times after infection. In addition to viral load measurements, antibody responses and latent reservoir sizes were measured. We estimate model parameters by fitting viral load measurements to the standard HIV viral dynamics model within a nonlinear fixed effects framework. This approach allows us to capture differences between rhesus macaques (RMs) that develop antibody responses or exhibit high latent reservoir sizes compared to those that do not. We find that neutralizing antibody responses are associated with increased viral clearance and decreased viral infectivity but decreased death rate of infected cells. In addition, the presence of detectable latent reservoir is associated with less robust immune responses. These results demonstrate that both immune response and latent reservoir dynamics are needed to understand post-rebound dynamics and point to the necessity of a comprehensive approach in tailoring personalized medical interventions.

immunology↗

Comparative Analysis of Within-Host Dynamics of Acute Infection and Viral Rebound Dynamics in Postnatally SHIV-Infected ART-Treated Infant Rhesus Macaques

Viral dynamics of acute HIV infection and HIV rebound following suspension of antiretroviral therapy may be qualitatively similar but must differ given, for one, development of adaptive immune responses. Understanding the differences of acute HIV infection and viral rebound dynamics in pediatric populations may provide insights into the mechanisms of viral control with potential implications for vaccine design and the development of effective targeted therapeutics for infants and children. Mathematical models have been a crucial tool to elucidate the complex processes driving viral infections within the host. Traditionally, acute HIV infection has been modeled with a standard model of viral dynamics initially developed to explore viral decay during treatment, while viral rebound has necessitated extensions of that standard model to incorporate explicit immune responses. Previous efforts to fit these models to viral load data have underscored differences between the two infection stages, such as increased viral clearance rate and increased death rate of infected cells during rebound. However, these findings have been predicated on viral load measurements from disparate adult individuals. In this study, we aim to bridge this gap, in infants, by comparing the dynamics of acute infection and viral rebound within the same individuals by leveraging an infant nonhuman primate Simian/Human Immunodeficiency Virus (SHIV) infection model. Ten infant Rhesus macaques (RMs) orally challenged with SHIV.C.CH505 375H dCT and given ART at 8 weeks post-infection. These infants were then monitored for up to 60 months post-infection with serial viral load and immune measurements. We use the HIV standard viral dynamics model fitted to viral load measurements in a nonlinear mixed effects framework. We find that the primary difference between acute infection and rebound is the increased death rate of infected cells during rebound. We use these findings to generate hypotheses on the effects of adaptive immune responses. We leverage these findings to formulate hypotheses to elucidate the observed results and provide arguments to support the notion that delayed viral rebound is characterized by a stronger CD8+ T cell response.

immunology↗

Identification and Characterization of Novel Metagenome Assembled Uncultivated Virus Genomes from Human Gut

Metagenomics has revealed an unprecedented viral diversity in human gut although, most of the sequence data remains to be characterized. In this study, we mined a collection of 1090 metagenome assembled "high quality" genomes of human gut viruses. Sequence analysis has revealed eight new species from seven genera of the class, Caudoviricetes and nineteen new species from fourteen genera of the ssDNA virus family, Microviridae. In addition, four "high quality" genomes were identified, which do not show similarity to sequences present in any of the four major viral databases, NCBI viral RefSeq, IMG-VR, Gut Phage Database (GPD) and Gut Virome Database (GVD). Further, annotation of the "high-quality" genomes and KEGG pathway analysis has identified antB, dnaB, DNMT1, DUT, xlyAB, xtmB and xtmA as the most widespread viral and Auxiliary Metabolic Genes (AMGs). Genes for virulence, host-takeover, drug resistance, tRNA, tmRNA and CRISPR elements were also found. Bacterial hosts are predicted for around 40% of the analyzed genomes. Overall, we report identification of new viral genomes and genome analyses of human gut viruses, which will be useful for biological characterization to establish their significance in physiology. IMPORTANCEMultiple studies have found that dysbiosis of gut virome is associated with conditions such as metabolic syndromes, autoimmune disorders and infectious diseases. In the interest of its therapeutic and diagnostic potential, intestinal virome warrants detailed investigation. However, limited ability to culture gut viruses becomes one of the challenges for their biological characterization and fully understanding their role in physiology. Sequence analysis and host prediction methods provide opportunities to understand gut viruses, their functional potential and devise ways for further characterization.

genomics↗

Large Language Models for Pathway Curation: A Preliminary Investigation

The pathway curation task involves analyzing scientific literature to identify and represent cellular processes as pathways. This process, often time-consuming and labor-intensive, requires significant curation efforts amidst the rapidly growing biomedical literature. Natural Language Processing (NLP) offers a promising method to automatically extract these interactions from scientific texts. Despite immense progress, there remains room for improvement in these systems. The emergence of Large Language Models (LLMs) provides a promising solution for this challenge. Our study conducts a preliminary investigation into leveraging LLMs for the pathway curation task. This paper first presents a review of the current state-of-the-art algorithms for the pathway curation task. Our objective is to check the feasibility and formulate strategies of using these LLMs to improve the accuracy of pathway curation task. Our experiments demonstrate that our GPT-3.5 based fine-tuned models outperforms existing state-of-the-art methods. Specifically, our model achieved a 10 basis point improvement in over-all recall and F1 score compared to the best existing algorithms. These findings highlight the potential of LLMs in pathway curation tasks, warranting further research and substantial efforts in this direction. Keypoints/ObjectivesO_LIStudy evaluates the feasibility of using Large Language Models (LLMs) for pathway curation in scientific literature. C_LIO_LIUsing GPT-3.5 based fine tuned models for pathway curation, we compare its performance with existing methods, focusing on precision, recall and F1 score metrics. C_LIO_LIEmphasize the promise and need for further research on using LLMs for pathway curation. C_LI

systems biology↗

Regulation of Diseases-Associated Microglia in the Optic Nerve by Lipoxin B4 and Ocular Hypertension

BackgroundThe resident astrocyte-retinal ganglion cell (RGC) lipoxin circuit is impaired during retinal stress, which includes ocular hypertension-induced neuropathy. Lipoxin B4 produced by homeostatic astrocytes directly acts on RGCs to increase survival and function in ocular hypertension-induced neuropathy. RGC death in the retina and axonal degeneration in the optic nerve are driven by the complex interactions between microglia and macroglia. Whether LXB4 neuroprotective actions include regulation of other cell types in the retina and/or optic nerve is an important knowledge gap. MethodsCellular targets and signaling of LXB4 in the retina were defined by single-cell RNA sequencing. Retinal neurodegeneration was induced by injecting silicone oil into the anterior chamber of the mouse eyes, which induced sustained and stable ocular hypertension. Morphological characterization of microglia populations in the retina and optic nerve was established by MorphOMICs and pseudotime trajectory analyses. The pathways and mechanisms of action of LXB4 in the optic nerve were investigated using bulk RNA sequencing. Transcriptomics data was validated by qPCR and immunohistochemistry. Differences between experimental groups were assessed by Students t-test and one-way ANOVA. ResultsSingle-cell transcriptomics identified microglia as a primary target for LXB4 in the healthy retina. LXB4 downregulated genes that drive microglia environmental sensing and reactivity responses. Analysis of microglial function revealed that ocular hypertension induced distinct, temporally defined, and dynamic phenotypes in the retina and, unexpectedly, in the distal myelinated optic nerve. Microglial expression of CD74, a marker of disease-associated microglia in the brain, was only induced in a unique population of optic nerve microglia, but not in the retina. Genetic deletion of lipoxin formation correlated with the presence of a CD74 optic nerve microglia population in normotensive eyes, while LXB4 treatment during ocular hypertension shifted optic nerve microglia toward a homeostatic morphology and non-reactive state and downregulated the expression of CD74. Furthermore, we identified a correlation between CD74 and phospho-phosphoinositide 3-kinases (p-PI3K) expression levels in the optic nerve, which was reduced by LXB4 treatment. ConclusionWe identified early and dynamic changes in the microglia functional phenotype, reactivity, and induction of a unique CD74 microglia population in the distal optic nerve as key features of ocular hypertension-induced neurodegeneration. Our findings establish microglia regulation as a novel LXB4 target in the retina and optic nerve. LXB4 maintenance of a homeostatic optic nerve microglia phenotype and inhibition of a disease-associated phenotype are potential neuroprotective mechanisms for the resident LXB4 pathway.

molecular biology↗

Medication Use is Associated with Distinct Microbial Features in Anxiety and Depression

This study investigated the relationship between gut microbiota and neuropsychiatric disorders (NPDs), specifically anxiety disorder (ANXD) and/or major depressive disorder (MDD), as defined by DSM-IV or V criteria. The study also examined the influence of medication use, particularly antidepressants and/or anxiolytics, classified through the Anatomical Therapeutic Chemical (ATC) Classification System, on the gut microbiota. Both 16S rRNA gene amplicon sequencing and shallow shotgun sequencing were performed on DNA extracted from 666 fecal samples from the Tulsa-1000 and NeuroMAP CoBRE cohorts. The results highlight the significant influence of medication use; antidepressant use is associated with significant differences in gut microbiota beta diversity and has a larger effect size than NPD diagnosis. Next, specific microbes were associated with ANXD and MDD, highlighting their potential for non-pharmacological intervention. Finally, the study demonstrated the capability of Random Forest classifiers to predict diagnoses of NPD and medication use from microbial profiles, suggesting a promising direction for the use of gut microbiota as biomarkers for NPD. The findings suggest that future research on the gut microbiotas role in NPD and its interactions with pharmacological treatments are needed.

microbiology↗

Binding of SARS-CoV-2 nucleocapsid protein to uninfected epithelial cells induces antibody-mediated complement deposition

SARS-CoV-2 infection triggers strong antibody response toward Nucleocapsid-Protein (NP), suggesting extracellular presence beyond its intra-virion RNA binding. Interestingly, NP was found to decorate infected and proximal uninfected cell-surfaces. Here, we propose a new mechanism through which extracellular NP on uninfected cells contributes to COVID-19 pathogenicity. We show that NP binds to cell-surface sulfated linear-glycosaminoglycans by spatial rearrangement of its RNA-binding sites facilitated by the flexible, positively charged, linker. Coating of uninfected lung-derived cells with purified NP attracted anti-NP-IgG from lung fluids and sera collected from COVID-19 patients. The magnitude of this immune recognition was significantly elevated in moderate compared to mild COVID-19 cases. Importantly, binding of anti-NP-IgG present in sera generated clusters that triggered C3b deposition by the classical complement pathway. Heparin analog enoxaparin outcompeted NP-binding, rescuing cells from anti-NP IgG-mediated complement deposition. Our findings unveil how extracellular NP may exacerbate COVID-19 tissue damage, and suggest leads for preventative therapy. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=105 SRC="FIGDIR/small/585388v1_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@1084e20org.highwire.dtl.DTLVardef@4126caorg.highwire.dtl.DTLVardef@159c610org.highwire.dtl.DTLVardef@da7b7f_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIIgG from patients sera target NP-bound cells resulting in complement activation C_LIO_LIThe flexible linker allows NP to both bind linear sulfated GAGs and wrap around RNA C_LIO_LIHeparin analogs prevent NP surface binding and alleviate complement activation C_LIO_LICell-ELISA anti-NP IgG levels differ between mild and moderate COVID-19 C_LI

immunology↗

Expression of Plasmodium Major Facilitator Superfamily Protein in Transporters-Delta Candida Identifies a Drug Transporter

AimTo assess the functional relevance of a putative Major Facilitator Superfamily (MFS) protein (PF3D7_0210300; "PfMFS_DT") as a drug transporter, using Candida glabrata for orthologous protein expression. MethodsCDS encoding PfMFS_DT was integrated into the genome of genetically engineered C. glabrata strain MSY8 via homologous recombination, followed by assessing its functional relevance as a drug transporter. Results and ConclusionThe modified C. glabrata strain exhibited plasma membrane localization of PfMFS_DT and characteristics of an MFS transporter, conferring resistance to antifungals, ketoconazole and itraconazole. The nanomolar inhibitory effects of the drugs on the intra-erythrocytic growth of P. falciparum highlight their antimalarial properties. This study proposes PfMFS_DT as a drug transporter, expanding the repertoire of the currently known antimalarial "resistome".

cell biology↗

A proteome-wide quantitative guide for nanoscale spatially resolved extraction of membrane proteins into native nanodiscs

The intricate molecular environment of the native membrane profoundly influences every aspect of membrane protein (MP) biology. Despite this, the most prevalent method of studying MPs uses detergent-like molecules that disrupt and remove this vital local membrane context. This severely impedes our ability to quantitatively decipher the local molecular context and comprehend its regulatory role in the structure, function, and biogenesis of MPs. Using a library of membrane-active polymers we have developed a platform for the high-throughput analysis of the membrane proteome. The platform enables near-complete spatially resolved extraction of target MPs directly from their endogenous membranes into native nanodiscs that maintain the local membrane context. We accompany this advancement with an open-access database that quantifies the polymer-specific extraction variability for 2065 unique mammalian MPs and provides the most optimized condition for each of them. Our method enables rapid and near-complete extraction and purification of target MPs directly from their endogenous organellar membranes at physiological expression levels while maintaining the nanoscale local membrane environment. Going beyond the plasma membrane proteome, our platform enables extraction from any target organellar membrane including the endoplasmic reticulum, mitochondria, lysosome, Golgi, and even transient organelles such as the autophagosome. To further validate this platform, we took several independent MPs and demonstrated how our resource can enable rapid extraction and purification of target MPs from different organellar membranes with high efficiency and purity. Further, taking two synaptic vesicle MPs, we show how the database can be extended to capture multiprotein complexes between overexpressed MPs. We expect these publicly available resources to empower researchers across disciplines to efficiently capture membrane nano-scoops containing a target MP and interface with structural, functional, and other bioanalytical approaches. We demonstrate an example of this by combining our extraction platform with single-molecule TIRF imaging to demonstrate how it can enable rapid determination of homo-oligomeric states of target MPs in native cell membranes.

biophysics↗

A dynamic WUSCHEL / Layer 1 interplay directs shoot apical meristem formation during regeneration

De novo shoot apical meristem (SAM) organogenesis during regeneration in tissue culture has been investigated for several decades, but the precise mechanisms governing early-stage cell fate specification remain elusive. In contrast to SAM establishment during embryogenesis, in vitro SAM formation occurs without positional cues, and is characterized by spontaneous cellular patterning. Here, we have elucidated the initial stages of SAM organogenesis and the molecular mechanisms that orchestrate gene patterning to establish SAM homeostasis. We found that SAM organogenesis in tobacco calli initiates with protuberance formation followed by the formation of an intact L1 layer covering the nascent protuberance. Acquisition of L1 cellular identity is indispensable for de novo SAM formation, which also requires WUSCHEL (WUS) and the cellular capacity to direct anticlinal cell divisions. An intriguing finding is that TONNEAU1 silencing prevents the exclusive occurrence of anticlinal divisions in the outermost layer of the protuberances and suppresses the acquisition of L1 cellular identity, ultimately impeding regeneration. This study exposes an intricate interplay between L1 and WUS expression and that any disruption in this interplay compromises shoot formation. It further provides a novel molecular framework for the characterization of WUS/L1 interplay-mediated shoot apical meristem formation during regeneration.

plant biology↗

Multiomics analysis reveals B. MO1 as a distinct Babesia species and provides insights into its evolution and virulence.

Babesiosis, caused by protozoan parasites of the genus Babesia, is an emerging tick-borne disease of significance for both human and animal health. Babesia parasites infect erythrocytes of vertebrate hosts where they develop and multiply rapidly to cause the pathological symptoms associated with the disease. The identification of various Babesia species underscores the ongoing risk of new zoonotic pathogens capable of infecting humans, a concern amplified by anthropogenic activities and environmental shifts impacting the distribution and transmission dynamics of parasites, their vectors, and reservoir hosts. One such species, Babesia MO1, previously implicated in severe cases of human babesiosis in the midwestern United States, was initially considered closely related to B. divergens, the predominant agent of human babesiosis in Europe. Yet, uncertainties persist regarding whether these pathogens represent distinct variants of the same species or are entirely separate species. We show that although both B. MO1 and B. divergens share similar genome sizes, comprising three nuclear chromosomes, one linear mitochondrial chromosome, and one circular apicoplast chromosome, major differences exist in terms of genomic sequence divergence, gene functions, transcription profiles, replication rates and susceptibility to antiparasitic drugs. Furthermore, both pathogens have evolved distinct classes of multigene families, crucial for their pathogenicity and adaptation to specific mammalian hosts. Leveraging genomic information for B. MO1, B. divergens, and other members of the Babesiidae family within Apicomplexa provides valuable insights into the evolution, diversity, and virulence of these parasites. This knowledge serves as a critical tool in preemptively addressing the emergence and rapid transmission of more virulent strains.

microbiology↗

DDHD2 is necessary for activity-driven fatty acid fueling of nerve terminal function

HSP54, a hereditary spastic paraplegia associated with cognitive impairment, is caused by mutations in the neuron-specific triglyceride (TG) lipase DDHD2. Loss of DDHD2 function results in lipid accumulation in human brains1 and lipid droplets (LDs) in mouse neurons2. In metabolically demanding tissues, TG lipases generate a fatty acid (FA) flux from LDs to fuel mitochondrial ATP production, but neurons are considered unable to use fat as an energy source. Thus, the basis for cognitive impairment driven by DDHD2 loss remains enigmatic. To resolve this paradox, we took advantage of presynaptic sensitivity to metabolic perturbations to determine if FAs derived from LDs could power local {beta}-oxidation to support synaptic functions and whether DDHD2 activity would be required in the process. We demonstrate that nerve terminals are enriched with DDHD2 and blocking its activity leads to presynaptic accumulation of LDs. Moreover, we show that FAs derived from axonal LDs enter mitochondria in an activity-dependent fashion and drive local mitochondrial ATP production allowing nerve terminals to sustain function in the complete absence of glucose. Our data demonstrate that neurons and their nerve terminals can make use of LDs during electrical activity to provide metabolic support when glucose is in short supply.

neuroscience↗

Unraveling molecular basis for reduced neuraminidase inhibitors susceptibility in highly pathogenic avian influenza A (H5N1) viruses isolated from chickens in India

The increasing resistance cases in influenza viruses to different classes of antiviral drugs, necessitates the in-depth analysis of molecular interactions governing reduced susceptibility to these drugs. This study explores the molecular basis of neuraminidase inhibitors resistance in avian H5N1 influenza viruses identified in our previous research. Using comprehensive modeling and docking tools, we investigated two isolates--A/chicken/India/85459/2008 (N294S) and A/chicken/WestBengal/142121/2008 (E119A + I117V). The N294S mutation conferred oseltamivir resistance while retaining zanamivir susceptibility, whereas the E119A + I117V mutations led to zanamivir resistance while reducing oseltamivir susceptibility. Molecular interactions analysis unveiled varied fitness levels, hydrogen bonding, and affinity transitions associated with N294S and E119A + I117V mutations. This study provides crucial insights into molecular interactions responsible for reduced susceptibility to neuraminidase inhibitors, which is essential for optimizing antiviral strategies and pandemic preparedness.

microbiology↗

Isolation and Lipidomic Profiling of Neuronal Lipid Droplets: Unveiling the Lipid Landscape for insights into Neurodegenerative Disorders

Recent advances have expanded the role of lipid droplets (LDs) beyond passive lipid storage, implicating their involvement in various metabolic processes across mammalian tissues. Neuronal LDs, whose existence has long been debated, have now been identified in several neural structures, raising questions about their contribution to neurodegenerative disorders. Elucidating the specific chemical makeup of these organelles within neurons is critical for understanding their role in neural pathologies. However, the inherent submicron size and low abundance in neurons have posed challenges in their isolation; and physical and biochemical characterization. Here, we present our protocol which overcomes this obstacle: we blocked neuron-specific triglyceride lipase to enlarge LDs, rendering them amenable to floatation in a sucrose gradient. We further employed an improved methodology of lipidomic analysis on the LDs purified from cultured primary neurons, offering insights into their unique lipid composition. This protocol can be implemented by researchers with basic expertise in neuronal culture, imaging, ultracentrifuge handling, and LC-MS analysis. The complete workflow requires 3-4 weeks, from neuronal culture to lipidomics analysis. Future integration of this method with high-throughput techniques holds promises for uncovering disease-specific alterations in lipid metabolism, providing new avenues for potential therapeutic interventions. Key pointsO_LIThis protocol describes a robust workflow for pharmacological induction, purification, and characterization of mature lipid droplets from primary cortical neurons without any detectable cytosolic membrane carryover. C_LIO_LILC-MS analysis of neuronal lipid droplets can reveal lipids previously uncharacterized by other methods, providing a platform to integrate high-throughput proteomics and other techniques for probing neurodegenerative disease linked metabolic alterations in neurons. C_LI Key referenceKumar, M. et al. Triglycerides are an important fuel reserve for synapse function in the brain. Nat Metab 7, 1392-1403 (2025). https://doi.org:10.1038/s42255-025-01321-x Editorial summaryThis protocol describes a robust workflow for pharmacological induction, purification, and characterization of mature lipid droplets from primary cortical neurons without any detectable cytosolic membrane carryover. Proposed teaserIsolation and lipidomic profiling of neuronal lipid droplets

biochemistry↗

Fast and scalable querying of eukaryotic linear motifs with gget elm

MotivationEukaryotic linear motifs (ELMs), or Short Linear Motifs (SLiMs), are protein interaction modules that play an essential role in cellular processes and signaling networks and are often involved in diseases like cancer. The ELM database is a collection of manually curated motif knowledge from scientific papers. It has become a crucial resource for cataloging motif biology and recognizing candidate ELMs in novel amino acid sequences. Users can search amino acid sequences or UniProt IDs on the ELM resource web interface. However, as with many web services, there are limitations in the swift processing of large-scale queries through the ELM web interface or API calls, and, therefore, integration into protein function analysis pipelines is limited. ResultsTo allow swift, large-scale motif analyses on protein sequences using ELMs curated on the ELM database, we have developed a Python and command line tool, gget elm, which relies on local computations for efficiently finding candidate ELMs in user-submitted amino acid sequences and UniProt identifiers. gget elm increases accessibility to the information stored in the ELM database and allows scalable searches for motif-mediated interaction sites in the amino acid sequences. Availability and implementationThe manual and source code are available at https://github.com/pachterlab/gget.

bioinformatics↗

Generation and characterization of a multi-functional panel of monoclonal antibodies for SARS-CoV-2 research and treatment

The Coronavirus disease 2019 (COVID19) pandemic caused by Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) is an ongoing threat to global public health. To this end, intense efforts are underway to develop reagents to aid in diagnostics, enhance preventative measures, and provide therapeutics for managing COVID-19. The recent emergence of SARS-CoV-2 Omicron variants with enhanced transmissibility, altered antigenicity, and significant escape of existing monoclonal antibodies and vaccines underlines the importance of the continued development of such agents. The SARS-CoV-2 spike protein and its receptor binding domain (RBD) are critical to viral attachment and host cell entry and are primary targets for antibodies elicited from both vaccination and natural infection. In this study, mice were immunized with two synthetic peptides (Pep 1 and Pep 2) within the RBD of the original Wuhan SARS-CoV-2, as well as the whole RBD as a recombinant protein (rRBD). Hybridomas were generated and a panel of three monoclonal antibodies, mAb CU-P1-1 against Pep 1, mAb CU-P2-20 against Pep 2, and mAb CU-28-24 against rRBD, were generated and further characterized. These mAbs were shown by ELISA to be specific for each immunogen/antigen. Monoclonal antibody CU-P1-1 has limited applicability other than in ELISA approaches and basic immunoblotting. Monoclonal antibody CU-P2-20 is shown to be favorable for ELISA, immunoblotting, and immunohistochemistry (IHC), however, not live virus neutralization. In contrast, mAb CU-28-24 is most effective at live virus neutralization as well as ELISA and IHC. Moreover, mAb CU-28-24 was active against rRBD proteins from Omicron variants B.2 and B.4/B5 as determined by ELISA, suggesting this mAb may neutralize live virus of these variants. Each of the immunoglobulin genes has been sequenced using Next Generation Sequencing, which allows the expression of respective recombinant proteins, thereby eliminating the need for long-term hybridoma maintenance. The synthetic peptides and hybridomas/mAbs are under the intellectual property management of the Clemson University Research Foundation, and the three CDRs have been submitted as an invention disclosure for further patenting and commercialization.

immunology↗

DystoGen Compendium: A comprehensive resource of ACMG annotated movement disorder associated genetic variants

PurposeIn recent years, the advent of high throughput sequencing techniques has led to the identification of a number of genetic variants across different genes that are associated with movement disorders. However, the under-appreciation of the variant spectrum in movement disorders and the lack of consolidated and systematic evidence-based annotation of these variants has long undermined the true potential of genomic approaches to expedite precision medicine. MethodsWe manually curated the genetic variants from a panel of 118 genes that have been associated with monogenic causes of movement disorders and systematically annotated them according to ACMG & AMP (American College of Medical Genetics and the Association of Molecular Pathologists) guidelines. ResultsData integration after systematic classification of variants according to ACMG & AMP guidelines showed 5118 pathogenic/likely pathogenic variants accounting for 18.03% of the total unique variants being annotated. This data and annotations are available in a comprehensive online compendium DystoGen. ConclusionTo the best of our knowledge, this is the most comprehensive compendium of genetic variants in movement disorders annotated as per the ACMG & AMP guidelines for pathogenicity. The compendium indexes 28377 variants along with a wide array of information including the geographical origin of the variant, global distribution, and population allele frequency. The resource has been made available in the URL https://clingen.igib.res.in/dystogen/.

bioinformatics↗