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Dutt, M.

Publications and source records attributed to Dutt, M..

9 recordsLinked to original sources

GenomeProt: User friendly proteogenomics for canonical and non-canonical proteoform characterisation

Quantifying the diversity of RNAs and proteins produced by cells is fundamental to the biological and clinical sciences. However, many RNAs and proteins remain uncharacterised, especially proteins translated from alternate RNA isoforms; untranslated regions of mRNAs and non-coding RNAs, as well as the effects of DNA variation on protein sequences. Proteogenomics aims to characterise the complete proteome by integrating genomics and/or transcriptomics with proteomics, but current tools have limitations in useability, analysis features and visualisation of resulting data. To address these gaps, we developed GenomeProt, a user-friendly GUI-based tool for integrative proteogenomic analysis. We demonstrate its utility by integrating long-read RNA sequencing with mass-spectrometry-based proteomics to pinpoint proteoform expression generated by alternative splicing; discover novel, unannotated proteins in human brain samples; and quantify variant-containing peptides associated with treatment resistance in a melanoma xenograft model. GenomeProt brings the discovery power of proteogenomics to biologists, illuminating the hidden proteome.

bioinformatics↗

Framework for Martini-based Coarse-grained Model of Enzymes: Model Development and Experimental Validation

Recent experiments have shown that enzyme activity can preserved in harsh environments by complexing enzyme with polymer into a Protein-Polymer Hybrid (PPH). In a successful PPH, heteropolymer strands bind to the enzyme surface and restrain the folded protein without adversely affecting the binding and active sites. It is believed that hybridization is driven by non-covalent interactions at the enzyme surface including hydrophobicity and electrostatics. Molecular modeling of these interactions is not practical at the all-atom scale due to the long timescales and large particle counts needed to characterize binding. Protein structure at the scale of amino acid residues is parsimoniously represented by a coarse-grained model in which one particle represents several atoms, significantly reducing the cost of simulation. In this study we present two coarse-grained enzyme models - lipase and dehalogenase - prepared using a top-down modeling strategy. We simulate each enzyme in aqueous solution and calculate statistics of protein surface features and shape descriptors. The values from the coarse-grained data are compared with the same calculations performed on all-atom reference systems, revealing key similarities of surface chemistry at the two scales. Structural measures are calculated from the all-atom reference systems and compared with estimates from small-angle X-ray scattering (SAXS) experiments, with good agreement between the two. The described procedures of modeling and analysis comprise a framework for the development of coarse-grained models of protein surfaces with validation to experiment.

biophysics↗

Advancing Tolerogenic Immunotherapy: A Multi-Epitope Vaccine Design Targeting the CYP2D6 Autoantigen in Autoimmune Hepatitis Through Immuno-Informatics

Juvenile autoimmune hepatitis (JAIH) is a rare autoimmune disorder affecting children, characterized by the immune systems misguided attack on liver cells, primarily targeting the CYP2D6 autoantigen. This repeated attack leads to hepatic inflammation, fibrosis, and eventual liver failure. Current therapeutic strategies predominantly rely on immunosuppressive agents or whole B cell depletion antibodies, which render patients susceptible to infections and cancers. Hence, there is an urgent need for antigen-specific therapies to mitigate the severity of autoimmune hepatitis. Tolerogenic antigens represent a promising avenue in immunotherapy, capable of dampening autoimmunity. Here, we present a novel computationally designed multi-epitope tolerogenic vaccine tailored to target CYP2D6, aimed at inducing tolerogenic dendritic cells (DCs) and halting autoimmune progression in JAIH patients. To validate our approach, we have developed a similar vaccine for testing in mouse models of JAIH. The selected tolerogenic epitopes exhibit antigenicity without allergenicity or toxicity, and specifically induce IL-10 production (restricted to CD4+ T cell epitopes). In our vaccine design, tolerogenic poly-epitopes are linked with Toll-like receptor (TLR)-4-agonist, the 50S ribosomal unit, and IL-10, effectively programming DCs towards a tolerogenic state. Molecular docking and dynamic simulations have confirmed strong binding affinities and stable complexes between the vaccine structures, TLR4 and IL-10 receptor alpha (IL-10RA), indicating their potential for in vivo DC interaction and programming. Consequently, this innovative vaccine approach demands further exploration through wet lab experiments to assess its tolerogenicity, safety, and efficacy, thereby laying the groundwork for potential application in clinical settings.

immunology↗

Unleashing the Immune Arsenal: Development of Broad-spectrum Multiepitope Bluetongue Vaccine Targeting Conserved T Cell Epitopes of Structural Proteins

Bluetongue (BT) is a severe arboviral disease affecting sheep, cows, and other wild ruminants, caused by the Bluetongue virus (BTV). The virus has evolved into over 32 serotypes, rendering existing vaccines less effective. While the structural proteins of this virus represent promising targets for vaccine development, they unfortunately exhibit high amino acid polymorphism and are laden with numerous inhibitory epitopes. Structural proteins such as VP1 and VP7 are highly conserved and may contain epitopes capable of triggering cross-reactive cell-mediated immunity (CMI). In this study, we identified highly conserved MHC-I and -II-restricted T cell epitopes within VP1, VP5, and VP7 BTV proteins and developed an effective in silico-immuno-informatics-based broad-spectrum BT multiepitope vaccine for bovine and laboratory mouse systems. The conserved epitopes utilized in the vaccines are highly antigenic, non-allergenic, non-toxic, and capable of inducing IFN-{gamma} (only CD4+ T cell epitopes). Both mouse and bovine vaccines were tethered with Toll-like receptor (TLR)-4-agonist adjuvants, beta-defensin 2, and the 50s ribosomal unit to stimulate innate immunity for CMI development. Protein-protein docking analysis revealed strong binding affinities, while extensive 100-nanosecond molecular dynamics simulations indicated stable complexes between the vaccine structures and TLR4. Vaccination simulation studies demonstrated their ability to trigger proinflammatory responses. Therefore, these novel vaccine designs necessitate further exploration through wet lab experiments to evaluate their immunogenicity, safety, and effectiveness for practical deployment in livestock.

immunology↗

Immuno-informatics Study Identifies Conserved T Cell Epitopes in Non-structural Proteins of Bluetongue Virus Serotypes: Formulation of Computationally Optimized Next-Generation Broad-spectrum Multiepitope Vaccine

Bluetongue (BT) is a significant arboviral disease affecting sheep, cattle, goats, and wild ruminants, posing serious economic challenges to livestock industry. Control efforts have been hampered by the existence of over 32 distinct BT virus (BTV) serotypes and the absence of broad-spectrum vaccines. Some key non-structural proteins of BTV, including NS1, NS2, and NS3, exhibit notable amino acid sequence conservation. Our findings reveal that mouse MHC class I (MHC-I) CD8+ T cell epitopes are highly conserved in NS1 and NS3, while MHC-II epitopes are prevalent in all the three non-structural NS 1-3 proteins. Similarly, both class I and II Bovine Leukocyte antigen-restricted CD8+ and CD4+ T cell epitopes are conserved within NS1, NS2, and NS3 proteins. To construct in silico broad-spectrum vaccine, we subsequently screened these conserved epitopes based on antigenicity, allergenicity, toxicity, and solubility. Modeling and Refinement of the 3D structure models of vaccine constructs were achieved using protein modeling web servers. Our analysis revealed promising epitopes that exhibit strong binding affinities with low energies against two TLR receptors (TLR3 and TLR4). To ensure atomic-level stability, we evaluated the docking complexes of epitopes and receptors through all-atom molecular dynamics simulations (MDS). Encouragingly, our 100 nanoseconds MDS showed stable complexes with minimal RMSF values. Our study offers valuable insights into these conserved T cell epitopes as promising candidates for a broad-spectrum BT vaccine. We therefore encourage for their evaluation in animal models and natural hosts to assess their immunogenicity, safety, and efficacy for field use in the livestock.

bioinformatics↗

Affinity purification-mass spectrometry and single fiber physiology/proteomics reveals mechanistic insights of C18ORF25

C18ORF25 was recently shown to be phosphorylated at S67 by AMP-activated protein kinase (AMPK) in skeletal muscle following acute exercise in humans. Phosphorylation was shown to improve ex vivo skeletal muscle contractile function in mice but our understanding of the molecular mechanisms is incomplete. Here, we profiled the interactome of C18ORF25 in mouse myotubes using affinity purification coupled to mass spectrometry. This analysis included an investigation of AMPK-dependent and S67-dependent protein:protein interactions. Several nucleocytoplasmic and contractile-associated proteins were identified, and revealed a subset of GTPases that associate with C18ORF25 in an AMPK- and S67 phosphorylation-dependent manner. We confirmed that C18ORF25 is localised to the nucleus and the contractile apparatus in skeletal muscle. Mice lacking C18Orf25 display defects in calcium handling specifically in fast-twitch muscle fibers. To investigate these mechanisms, we developed an integrated single fiber physiology and single fiber proteomic platform. The approach enabled detailed assessment of various steps in the excitation-contraction (EC) pathway including SR calcium handling and force generation followed by paired single fiber proteomic analysis. This enabled us to identify >700 protein:phenotype associations and 36 fiber-type specific differences following loss of C18Orf25. Taken together, our data provide unique insights into the function of C18ORF25 and its role in skeletal muscle physiology.

physiology↗

PoxiPred: An artificial intelligence-based method for the prediction of potential antigens and epitopes to accelerate vaccine development efforts against poxviruses.

MotivationPoxviridae is a family of large, complex, enveloped, and double-stranded DNA viruses. Members of this family are ubiquitous and well known to cause contagious diseases in humans and other types of animals as well. Despite significant progress in Artificial intelligence (AI) based methods, limited methods are available to predict the epitopes. In this study, we have proposed a unique method to predict the potential antigens and T-cell epitopes for multiple poxviruses. ResultsWith PoxiPred, we developed an AI-based tool that was trained and tested with antigens and epitopes of Poxviruses. Our tool was able to locate 1,675 antigen proteins from 25 distinct poxviruses. From these antigenic proteins, PoxiPred also located 6,579 T-cell epitopes. PoxiPred is able to, on a single run, identify antigens and T-cell epitopes for poxviruses with one single input, i.e., the proteome file of any poxvirus. AvailabilityThe code that implements PoxiPred and the predicted antigens/T-cell epitopes is publicly available at https://github.com/gustavsganzerla/poxipred.

bioinformatics↗

Phloem transport limitation in Huanglongbing affected sweet orange is dependent on phloem-limited bacteria and callose

Huanglongbing (HLB), caused by Candidatus Liberibacter asiaticus (CLas), is a phloem-limited disease which disrupts citrus production in affected areas. In HLB-affected plants, phloem sieve plate pores accumulate callose, and leaf carbohydrate export is reduced. However, whether HLB causes a reduction in carbohydrate phloem translocation speed, and the quantitative relationships among callose, CLas population, and phloem translocation are still unknown. In this work, a procedure was developed to concurrently measure sugar transport, callose deposition, and relative pathogen population at different locations throughout the stem. Increasing quantities of CLas genetic material were positively correlated with quantity and density of callose deposits, and negatively correlated with phloem translocation speed. Callose deposit quantity was site- and rootstock dependent, and were negatively correlated with phloem translocation speed, suggesting a localized relationship. Remarkably, callose accumulation and phloem translocation disruption in the scion was dependent on rootstock genotype. Regression results suggested that the interaction of Ct values and number of phloem callose depositions, but not their size or density, explained the effects on translocation speed. Sucrose, starch, and sink 14C label allocation data support the interpretation of a transport pathway limitation by CLas infection. This work shows that the interaction of local accumulation of callose and CLas affect phloem transport. Further, the extent of this accumulation is attenuated by the rootstock and provides important information about the disease mechanism of phloem-inhabiting bacteria. Together, these results constitute the first example of a demonstrated transport limitation of phloem function by a microbial infection.

plant biology↗

Marizomib suppresses triple-negative breast cancer via proteasome and oxidative phosphorylation inhibition

Lacking effective targeted therapies, triple-negative breast cancer (TNBCs) is highly aggressive with development of metastasis especially brain, and remains clinically challenging breast cancer subtype to treat. Despite the survival dependency on the proteasome pathway genes, FDA-approved proteasome inhibitors induced minimal clinical response in breast cancer patients due to weak proteasome inhibition. Here, we show that a potent proteasome inhibitor Marizomib (Mzb) inhibits multiple proteasome catalytic activities and induces a better anti-tumor response in TNBC cell lines and patient-derived xenografts alone and in combination with the standard-of-care chemotherapy. Mechanistically, Mzb inhibits oxidative phosphorylation (OXPHOS) via PGC-1 suppression in conjunction with proteasome inhibition in TNBC cells. Mzb reduces lung and brain metastases by reducing the number of circulating tumor cells and the expression of multiple genes involved in the epithelial-to-mesenchymal transition. Furthermore, Mzb-induced OXPHOS inhibition upregulates glycolysis to meet the energetic demands of TNBC cells and, hence, combined inhibition of glycolysis with Mzb exposure leads to a synergistic anti-cancer activity. Collectively, our data provide a strong rationale for a clinical evaluation of Mzb in primary and metastatic TNBC patients.\n\nOne Sentence SummaryMarizomib inhibits primary tumor growth, and also reduces lung and brain metastases in pre-clinical models of triple-negative breast cancer.

cancer biology↗