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Vinogradova, E. V.

Publications and source records attributed to Vinogradova, E. V..

7 recordsLinked to original sources

Chemical proteomics reveals post-translational remodeling of endosomal pathways during macrophage activation.

Macrophages are central regulators of innate immunity, yet the post-translational mechanisms that enable rapid inflammatory responses remain incompletely understood. Here, we integrated transcriptomics, unenriched proteomics, phosphoproteomics, metabolomics, and cysteine reactivity profiling to comprehensively characterize primary human macrophages following Toll-like receptor and Stimulator of Interferon Genes (STING) activation. This approach revealed substantial discordance between transcript- and protein-level changes, as well as extensive post-translational remodeling. Differentially reactive cysteines were enriched in proteins involved in small-GTPase signaling, vesicular trafficking, and the endo-lysosomal system. Reactivity changes in two subunits of the endosomal mRNA-transport FERRY complex nominated it as a candidate target of inflammation-associated post-translational regulation. Biochemical and imaging analyses established FERRY complex assembly and early endosomal localization in primary human macrophages and identified DISC1 as a previously unrecognized FERRY-associated protein. This work provides a comprehensive resource of biochemical and post-translational remodeling during macrophage activation and implicates endosome-associated mRNA transport in innate immune regulation.

immunology↗

A post-translational regulatory map of chronic antigen-driven human T cell dysfunction.

T cells exposed to persistent antigen in the context of chronic viral infections or cancer lose self-renewal and cytotoxic capacity. Several transcriptional, epigenetic, and metabolic drivers of this process have been identified. However, the post-transcriptional regulatory mechanisms influencing the proteome of dysfunctional T cells are not well understood. Here we present a time-resolved molecular landscape of human T cells during the development of chronic antigen-driven dysfunction. Persistent T cell receptor stimulation significantly remodeled the proteome, including changes in canonical T cell exhaustion-associated proteins and proteins related to mitochondrial function, redox homeostasis, nucleotide metabolism, and cell-cycle progression. Dysfunctional T cells displayed activation of stress response pathways that were recapitulated in vivo; targeting these pathways altered the cytotoxic capacity of T cells during persistent tumor exposure. Our comprehensive proteomic resource reveals unique post-transcriptional changes in dysfunctional T cells and lays the groundwork for novel cysteine-directed therapeutics to enhance cancer immunotherapy.

immunology↗

SLC33A1 exports oxidized glutathione to maintain endoplasmic reticulum redox homeostasis

The endoplasmic reticulum (ER) requires an oxidative environment to support the efficient maturation of secretory and membrane proteins. This is in part established by glutathione, a redox-active metabolite present in reduced (GSH) and oxidized (GSSG) forms. The ER maintains a higher GSSG:GSH ratio than the cytosol; however, the mechanisms controlling ER redox balance remain poorly understood. To address this, we developed a method for the rapid immunopurification of the ER, enabling comprehensive profiling of its proteome and metabolome. Combining this approach with CRISPR screening, we identified SLC33A1 as the major ER GSSG exporter in mammalian cells. Loss of SLC33A1 leads to GSSG accumulation in the ER and a liposome-based assay demonstrates that SLC33A1 directly transports GSSG. Cryo-EM structures and molecular dynamics simulations reveal how SLC33A1 binds GSSG and identify residues critical for its transport. Finally, an imbalance in GSSG:GSH ratio induces ER stress and dependency on the ER-associated degradation (ERAD) pathway, driven by a shift in protein disulfide isomerases (PDIs) toward their oxidized forms. Altogether, our work establishes SLC33A1-mediated GSSG export as a key mechanism for ER redox homeostasis and protein maturation.

cell biology↗

Cell type-specific proximity labeling of organ secretomes reveals energy balance-dependent proteomic remodeling.

Intercellular communication is critical for maintaining organismal metabolic homeostasis. Here, we present a new method enabling temporally controlled, cell type-specific labeling of secreted and membrane proteins in key metabolic tissues. The method employs a genetically encoded proximity-labeling strategy by targeting a Cre-dependent TurboID ligase to the endoplasmic reticulum (ER) in ES cell-derived mice. Expression of TurboID in liver, adipose tissue, and spleen enabled the characterization of organ-specific ER proteomes at baseline and in response to fasting, inflammation, and dietary obesity, revealing tissue-and perturbation-specific changes and augmenting our understanding of how the proteomes of individual tissues change to regulate systemic energy balance. This comprehensive resource represents an important advance toward understanding both how cell-to-cell communication changes in response to energy homeostasis and how it contributes to these alterations. This method is broadly applicable and provides a means for identifying biomarkers and therapeutic targets across a wide range of tissues.

physiology↗

Exercise intensity modulates the human plasma secretome and interorgan communication

Exercise is recognized as first-line therapy for many cardiometabolic diseases, including obesity, type 2 diabetes, and hypertension. Despite the abundant health-promoting effects of exercise, in-depth characterization of circulatory factors that mediate these benefits in humans remains incomplete. Moreover, how different modes and intensities of exercise uniquely regulate these processes is unclear. Here, we address these questions by conducting a multi-cohort human exercise intervention, incorporating sprint-interval exercise (SIE) and moderate-intensity exercise (MIE) to analyze intensity-dependent regulation of interorgan crosstalk. We find that exercise intensity distinctly influences the plasma proteome and metabolome in both untrained and trained participants. SIE led to immediate and robust changes to the plasma proteome, whereas MIE resulted in delayed secretory kinetics. By leveraging large, multi-organ gene and protein expression datasets, in combination with in vitro and in vivo tissue sampling, we map the differentially regulated proteins to their predicted tissue of origin and destination. We find that adipocytes are particularly sensitive to exercise intensity, undergoing broad transcriptomic remodeling following in vitro incubation with SIE as compared to MIE plasma. These findings underscore the integrated whole-body response following acute exercise and highlight exercise intensity as a key factor influencing interorgan communication.

physiology↗

Covalent Targeting of Splicing in T Cells.

Despite significant interest in therapeutic targeting of splicing, few chemical probes are available for the proteins involved in splicing. Here, we show that elaborated stereoisomeric acrylamide chemical probe EV96 and its analogues lead to a selective T cell state-dependent loss of interleukin 2-inducible T cell kinase (ITK) by targeting one of the core splicing factors SF3B1. Mechanistic investigations suggest that the state-dependency stems from a combination of differential protein turnover rates and availability of functional mRNA pools that can be depleted due to extensive alternative splicing. We further introduce a comprehensive list of proteins involved in splicing and leverage both cysteine- and protein-directed activity-based protein profiling (ABPP) data with electrophilic scout fragments to demonstrate covalent ligandability for many classes of splicing factors and splicing regulators in primary human T cells. Taken together, our findings show how chemical perturbation of splicing can lead to immune state-dependent changes in protein expression and provide evidence for the broad potential to target splicing factors with covalent chemistry.

immunology↗

Using a function-first "scout fragment"-based approach to develop allosteric covalent inhibitors of conformationally dynamic helicase mechanoenzymes

Helicases, classified into six superfamilies, are mechanoenzymes that utilize energy derived from ATP hydrolysis to remodel DNA and RNA substrates. These enzymes have key roles in diverse cellular processes, such as genome replication and maintenance, ribosome assembly and translation. Helicases with essential functions only in certain cancer cells have been identified and helicases expressed by certain viruses are required for their pathogenicity. As a result, helicases are important targets for chemical probes and therapeutics. However, it has been very challenging to develop selective chemical inhibitors for helicases, enzymes with highly dynamic conformations. We envisioned that electrophilic scout fragments, which have been used for chemical proteomic based profiling, could be leveraged to develop covalent inhibitors of helicases. We adopted a function-first approach, combining enzymatic assays with enantiomeric probe pairs and mass spectrometry, to develop a covalent inhibitor that selectively targets an allosteric site in SARS-CoV-2 nsp13, a superfamily-1 helicase. Further, we demonstrate that scout fragments inhibit the activity of two human superfamily-2 helicases, BLM and WRN, involved in genome maintenance. Together, our findings suggest a covalent inhibitor discovery approach to target helicases and potentially other conformationally dynamic mechanoenzymes.

biochemistry↗