PacL1-ALFA tag based proximity proteomics in Mycobacterium tuberculosis
Ontology highlight
ABSTRACT: Proteomic analysis of peptides in close association to PacL1 under replete metal conditions (Sauton’s media), in Mycobacterium Tuberculosis (Erdman strain).
Project description:In this study we demonstrate the effect of oncolytic adenoviruses armed with CXCL9, CXCL10 and IL-15 to infect cancer cells, secrete the encoded protein and drive gradient-dependent T-cell attraction. Our in vivo validation demonstrated an increased intratumoral CD4+ and CD8+ T-cell infiltration following treatment with armed viruses compared to control groups. Finally, RCC cells were screened for tumor-specific peptides to validate their immunogenicity in a (personalized) oncolytic cancer vaccine approach, previously referred to as PeptiCRAd.
Project description:LD3 knock out cells were generated in HEK293T and HMC3 cells. Proteomics was done to test if they have any significant changes in the abundance of proteins that metabolize sugar lipids like gangliosides.
Project description:This part of the data submission of PXD046505. LD3 knock out cells were generated in HEK293T and HMC3 cells. Proteomics was done to test if they have any significant changes in the abundance of proteins that metabolize sugar lipids like gangliosides.
Project description:Oral transmission of T. cruzi is probably the most frequent mechanism among animals in the wild. In this context, there is a high prevalence of human infections in regions where triatomine infection with T. cruzi is low. This led to the hypothesis that the consumption of raw or undercooked meat from animals infected with T. cruzi could be responsible for the transmission of the infection. Therefore, the general objective of this study was to demonstrate the role of meat consumption from infected animals in the oral transmission of T. cruzi infection. Groups of five female mice Balb/c were fed with muscles obtained from mice in the acute phase of infection by the clone H510 C8C3hvir of T. cruzi, and the infection of the fed mice was monitored by a parasitemia curve. Similarly, we assessed the infective capacity of T. cruzi trypomastigotes and amastigotes by infecting groups of five mice Balb/c females, which were infected orally using a nasogastric probe, and the infection was monitored by parasitemia curve. Finally, different trypomastigote and amastigote inoculums were used to determine their infective capacity. Adhesion assays of T. cruzi proteins to AGS stomach cells were performed and the adhered proteins were detected by western blotting using monoclonal or polyclonal antibodies. In all cases, 60–100% of animals were fed meat from mice infected in the acute phase or infected by means of a nasogastric probe with trypomastigotes or amastigotes. These animals developed high parasitemia, and 80% died around day 40 post-infection. The adhesion tests showed that cruzipain is a molecule of trypomastigotes and amastigotes that binds to AGS cells. LC-MS/MS also confirmed that transialidase may be involved in TCT attachment of TCT or invasion of stomach cells. It was concluded that the consumption of meat from infected animals in the acute phase of T. cruzi infection allows transmission of the infection. Similarly, trypomastigotes and amastigotes were able to infect mice when administered orally, while cruzipain was a relevant molecule in this infective process.
Project description:A microfluidics technology was implemented to the immunoaffinity purification process of MHC peptides in Ligandomics/Immunopeptidomics. The thus purified HLA peptides were analysed by LCMS with the nanoElute LC and TimsTOF Pro Mass Spectrometer from Bruker. The aim of the microfluidics implementation was to improve the sensitivity and robustness while also reducing antibody and other material requirements in the immunoaffinity purification protocol.
Project description:Protein ubiquitination controls diverse processes within eukaryotic cells, including protein degradation, and is often dysregulated in diseases1. Moreover, protein degraders that redirect ubiquitination activities toward disease targets are an emerging and promising therapeutic class2. Over 600 E3 ubiquitin ligases are expressed in humans3,4, but their substrates remain largely elusive due to a lack of robust methods to identify E3 ligase substrates. Here we report the development of E-STUB (E3 substrate tagging by ubiquitin biotinylation), a ubiquitin-specific proximity labeling method that biotinylates ubiquitinated substrates in proximity to an E3 ligase of interest. E-STUB accurately identifies the direct ubiquitinated targets of protein degraders, including collateral targets and ubiquitylation events that do not exhibit a degradative outcome. It also detects known substrates of E3 ligase cereblon (CRBN) and von Hippel-Lindau (VHL) with high precision. With the ability to elucidate proximal ubiquitination events, E-STUB may facilitate the development of proximity-inducing drugs and act as a generalizable method for E3 substrate mapping.
Project description:Protein ubiquitination controls diverse processes within eukaryotic cells, including protein degradation, and is often dysregulated in diseases1. Moreover, protein degraders that redirect ubiquitination activities toward disease targets are an emerging and promising therapeutic class2. Over 600 E3 ubiquitin ligases are expressed in humans3,4, but their substrates remain largely elusive due to a lack of robust methods to identify E3 ligase substrates. Here we report the development of E-STUB (E3 substrate tagging by ubiquitin biotinylation), a ubiquitin-specific proximity labeling method that biotinylates ubiquitinated substrates in proximity to an E3 ligase of interest. E-STUB accurately identifies the direct ubiquitinated targets of protein degraders, including collateral targets and ubiquitylation events that do not exhibit a degradative outcome. It also detects known substrates of E3 ligase cereblon (CRBN) and von Hippel-Lindau (VHL) with high precision. With the ability to elucidate proximal ubiquitination events, E-STUB may facilitate the development of proximity-inducing drugs and act as a generalizable method for E3 substrate mapping.
Project description:Protein ubiquitination controls diverse processes within eukaryotic cells, including protein degradation, and is often dysregulated in diseases1. Moreover, protein degraders that redirect ubiquitination activities toward disease targets are an emerging and promising therapeutic class2. Over 600 E3 ubiquitin ligases are expressed in humans3,4, but their substrates remain largely elusive due to a lack of robust methods to identify E3 ligase substrates. Here we report the development of E-STUB (E3 substrate tagging by ubiquitin biotinylation), a ubiquitin-specific proximity labeling method that biotinylates ubiquitinated substrates in proximity to an E3 ligase of interest. E-STUB accurately identifies the direct ubiquitinated targets of protein degraders, including collateral targets and ubiquitylation events that do not exhibit a degradative outcome. It also detects known substrates of E3 ligase cereblon (CRBN) and von Hippel-Lindau (VHL) with high precision. With the ability to elucidate proximal ubiquitination events, E-STUB may facilitate the development of proximity-inducing drugs and act as a generalizable method for E3 substrate mapping.
Project description:Small molecules that induce protein-protein interactions to exert proximity-driven pharmacology such as targeted protein degradation are a powerful class of therapeutics1-3. Molecular glues are of particular interest given their favorable size and chemical properties and represent the only clinically approved degrader drugs4-6. The discovery and development of molecular glues for novel targets, however, remains challenging. Covalent strategies could in principle facilitate molecular glue discovery by stabilizing the neo-protein interfaces. Here, we present structural and mechanistic studies that define a trans-labeling covalent molecular glue mechanism, which we term “template-assisted covalent modification”. We found that a novel series of BRD4 molecular glue degraders act by recruiting the CUL4DCAF16 ligase to the second bromodomain of BRD4 (BRD4BD2). BRD4BD2, in complex with DCAF16, serves as a structural template to facilitate covalent modification of DCAF16, which stabilizes the BRD4-degrader-DCAF16 ternary complex formation and facilitates BRD4 degradation. A 2.2 Å cryo-electron microscopy structure of the ternary complex demonstrates that DCAF16 and BRD4BD2 have pre-existing structural complementarity which optimally orients the reactive moiety of the degrader for DCAF16Cys58 covalent modification. Systematic mutagenesis of both DCAF16 and BRD4BD2 revealed that the loop conformation around BRD4His437, rather than specific side chains, is critical for BD2 selectivity. Supporting a general applicability, we find that a subset of compounds leads to a drug-induced GAK-BRD4 interaction stabilized by covalent modification of GAK. Together our work establishes “template-assisted covalent modification” as a mechanism for covalent molecular glues, which opens a new path to proximity driven pharmacology.
Project description:Structure formation of membrane proteins is error-prone and thus requires chaperones that oversee this essential process in cell biology. The ER membrane protein complex (EMC) is well-defined as a transmembrane domain (TMD) integrase. In this study, we characterize an additional chaperone function of the EMC. We use interactomics and systematic studies with model proteins to comprehensively define client features for this EMC chaperone mode. Based on this data, we develop a machine learning tool for client prediction. Mechanistically, our study reveals that the EMC engages TMDs via its EMC1 subunit and modulates their orientation within the lipid bilayer. Productive TMD assembly reduces binding to the EMC chaperone site. Taken together, our study provides detailed insights into an EMC chaperone function, further establishing the role of the EMC as a multifunctional molecular machine in membrane protein biogenesis.