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Jadhav, A. M.

Publications and source records attributed to Jadhav, A. M..

4 recordsLinked to original sources

Post-Translational Modifications Remodel Proteome-Wide Ligandability

Post-translational modifications (PTMs) vastly expand the diversity of human proteome, dynamically reshaping protein activity, interactions, and localization in response to environmental, pharmacologic, and disease-associated cues. While it is well established that PTMs modulate protein function, structure, and biomolecular interactions, their proteome-wide impact on small-molecule recognition--and thus druggability--remains largely unexplored. Here, we introduce a chemical proteomic strategy to delineate how PTM states remodel protein ligandability in human cells. By deploying broad profiling photoaffinity probes, we identified over 400 functionally diverse proteins whose ability to engage small molecules is impacted by phosphorylation or N-linked glycosylation status. Integration of binding site mapping with structural analyses revealed a diverse array of PTM-dependent pockets. Among these targets, we discovered that the phosphorylation status of common oncogenic KRAS mutants impact the action of small molecules, including clinically approved inhibitors. These findings illuminate an underappreciated, PTM-governed layer of proteome plasticity and uncover opportunities for the development of chemical probes to selectively target proteins in defined modification states.

biochemistry↗

Proteome-Wide Discovery of Degradable Proteins Using Bifunctional Molecules

Targeted protein degradation (TPD) is an emergent therapeutic strategy with the potential to circumvent challenges associated with targets unamenable to conventional pharmacological inhibition. Among TPD approaches, Proteolysis Targeting Chimeras (PROTACs) have shown marked advancement with numerous candidates in clinical development. Despite their potential, most PROTACs utilize advanced small molecule inhibitors, inherently limiting the scope of this approach. More generally, the fraction of the proteome tractable to PROTAC-type strategies is unknown. Here, we describe a chemical proteomic strategy for the agnostic discovery of degradable human proteins in cells using a new class of bifunctional degrader molecules called "AgnoTACs". Proteome-wide screening of 72 AgnoTACs in human cells uncovered downregulation events spanning >50 functionally and structurally diverse proteins, most of which lack chemical probes. Our findings highlight the potential of function-biased chemical libraries coupled with proteomic profiling to discover degrader starting points as well as furnish a blueprint for expanding our understanding of the chemically degradable proteome.

biochemistry↗

Chemoproteomics-guided Development of SLC15A4 Inhibitors with Anti-inflammatory Activity

SLC15A4 is an endolysosome-resident transporter that is intimately linked with autoinflammation and autoimmunity. Specifically, SLC15A4 is critical for Toll-like receptor (TLR) 7, 8, and 9 as well as the nucleotide-binding oligomerization domain-containing protein (NOD) 2 signaling in several immune cell subsets. Notably, SLC15A4 is essential for the development of systemic lupus erythematosus in murine models and is associated with autoimmune conditions in humans. Despite its therapeutic potential, to our knowledge no pharmacological tools have been developed that target SLC15A4. Here, we use an integrated chemical proteomics approach to develop a suite of chemical tools, including first-in-class functional inhibitors, for SLC15A4. We demonstrate SLC15A4 inhibitors suppress endosomal TLR and NOD functions in a variety of human and mouse immune cells and provide early evidence of their ability to suppress inflammation in vivo and in clinical settings. Our findings establish SLC15A4 as a druggable target for the treatment of autoimmune/autoinflammatory conditions. One-Sentence SummaryDiscovery and characterization of SLC15A4 inhibitors with anti-inflammatory activity.

immunology↗

Targeted Protein Acetylation in Cells Using Heterobifunctional Molecules

Protein acetylation is a central event in orchestrating diverse cellular processes. However, current strategies to investigate protein acetylation in cells are often non-specific or lack temporal and magnitude control. Here, we developed an acetylation tagging system, AceTAG, to induce acetylation of targeted proteins. The AceTAG system utilizes bifunctional molecules to direct the lysine acetyltransferase p300/CBP to proteins fused with the small protein tag FKBP12F36V, resulting in their induced acetylation. Using AceTAG, we induced targeted acetylation of a diverse array of proteins in cells, specifically histone H3.3, the NF-{kappa}B subunit p65/RelA, and the tumor suppressor p53. We demonstrate that targeted acetylation with the AceTAG system is rapid, selective, reversible, and can be controlled in a dose-dependent fashion. AceTAG represents a useful strategy to modulate protein acetylation and will enable the exploration of targeted acetylation in basic biological and therapeutic contexts. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=67 SRC="FIGDIR/small/454011v1_ufig1.gif" ALT="Figure 1"> View larger version (19K): org.highwire.dtl.DTLVardef@e7eeddorg.highwire.dtl.DTLVardef@f2fbf1org.highwire.dtl.DTLVardef@7a9d23org.highwire.dtl.DTLVardef@1e2a5b4_HPS_FORMAT_FIGEXP M_FIG C_FIG

biochemistry↗