Dataset Information

Cortisol binding sites on SARS-CoV-2 S1 identified by limited proteolysis-coupled mass spectrometry

ABSTRACT: We used a limited proteolysis-coupled mass spectrometry approach to pinpoint binding sites of cortisol on SARS-CoV-2 S1. Binding target identification is based on the principle that small-ligand binding alters (increases or decreases) the protease accessibility of the target protein37,38. The binding of the ligand (cortisol) to the target protein (SARS-CoV-2 S1) induces perturbations/conformational changes at the binding sites which can lead to either facilitating or preventing proteolysis by non-specific proteases (thermolysin and trypsin)37,38. We subjected SARS-CoV-2 S1 incubated with either cortisol or vehicle to proteolysis by thermolysin followed by trypsin digestion and mass spectrometry-based identification of the resultant peptides. We found that cortisol either facilitated or prevented S1 proteolytic cleavage at discrete sites. Six unique peptides were identified that were only present for SARS-CoV-2 S1 incubated with either cortisol or vehicle.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Severe Acute Respiratory Syndrome Coronavirus 2

DISEASE(S): Covid-19

SUBMITTER: Carlos Fernandez-Patron

LAB HEAD: Carlos Fernandez-Patron

PROVIDER: PXD032937 | Pride | 2022-06-10

REPOSITORIES: Pride

ACCESS DATA

Similar Datasets

Project description:Proteomics, the temporal study of proteins expressed by an organism, is a powerful technique that can reveal how organisms respond to biological perturbations, such as disease and environmental stress. Yet, the use of proteomics for addressing ecological questions has been limited, partly due to inadequate protocols for the sampling and preparation of animal tissues from the field. Although RNAlater is an ideal alternative to freezing for tissue preservation in transcriptomics studies, its suitability for the field could be more broadly examined. Moreover, existing protocols require samples to be preserved immediately to maintain protein integrity, yet the effects of delays in preservation on proteomic analyses have not been thoroughly tested. Hence, we optimised a proteomic workflow for wild-caught samples. First, we conducted a preliminary in-lab test using SDS-PAGE analysis on aquaria-reared Octopus berrima confirming that RNAlater can effectively preserve proteins up to 6 h after incubation, supporting its use in the field. Subsequently, we collected arm tips from wild-caught Octopus berrima and preserved them in homemade RNAlater immediately, 3 h, and 6 h after euthanasia. Processed tissue samples were analysed by liquid chromatography tandem mass spectrometry to ascertain protein differences between time delay in tissue preservation, as well as the influence of sex, tissue type, and tissue homogenisation methods. Over 3500 proteins were identified from all tissues, with bioinformatic analysis revealing protein abundances were largely consistent regardless of sample treatment. However, nearly 10 % additional proteins were detected from tissues homogenised with metal beads compared to liquid nitrogen methods, indicating the beads were more efficient at extracting proteins. Our optimised workflow demonstrates that sampling non-model organisms from remote field sites is achievable and can facilitate extensive proteomic coverage without compromising protein integrity.

Project description:Ubash3b, also known as suppressor of T-cell receptor signaling or Sts-1, is an ill-studied atypical tyrosine phosphatase with ubiquitin binding ability. In our previous study, we hypothesized that Ubash3b plays an inhibitory role in BCR-ABL signaling through binding and dephosphorylating BCR-ABL and its interactors. The Hantschel lab recently solved the crystal structures of the p210 PH and DH domains, which are absent in the p190 variant, and demonstrated that loss-of-function mutations in the PH domain altered BCR-ABL localization, thereby reducing the interaction between Ubash3b and p2104. Taken together, this suggests differential subcellular localization of Ubash3b as a mechanism by which it interacts more strongly with p201 as compared to p190. To better understand the global impact Ubash3b has on p210, its direct kinase substrates and proteins in its phosphotyrosine signaling network, we have taken an integrative approach by combining global phosphotyrosine profiling, proximity-dependent biotinylation (BioID) and total protein analysis to investigate p210 signaling upon Ubash3b knockdown (KD). The BioID system was used to characterize Ubash3b function in p210 signaling by examining its interactome. Importantly, in all of our BioID experiments, we employed a newly technique that we have recently developed, Biotinylation Site Identification Technology (BioSITe), which directly identifies biotinylated peptides thereby increasing the reliability of the identified interactors. Here, we additionally used short hairpin RNA (shRNA) interference and generated Ubash3b knock-down (KD) and non-targeting control shRNA lines in Ba/F3 BirA*-p210 cells. Ubash3b expression was reduced >90 % in the KD cells and had a substantial effect on global tyrosine phosphorylation and on the interactome of p210. Of the 1,421 unique tyrosine phosphorylation sites identified from 830 proteins, 379 sites (from 286 proteins) exhibited a substantial increase (ÃƒÂ¢Ã¢â‚¬Â°Ã‚Â¥2-fold) in tyrosine phosphorylation upon Ubash3b KD cells compared to control cells. To date, the interactome of Ubash3b has not been extensively investigated, however, some examination of Ubash3b in the context p210 signaling has been undertaken. We designed constructs of C-terminal BirA* tagged full length Ubash3b and a deletion mutant lacking the UBA and SH3 domains leaving only the phosphatase domain tethered to BirA*. A comparative analysis of the core interactors of p210 from previous studies and Ubash3b interactome from the current study revealed 36 proteins that interact with both p210 and Ubash3b.

Dataset Information

Cortisol binding sites on SARS-CoV-2 S1 identified by limited proteolysis-coupled mass spectrometry

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure