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Bellina, B.

Publications and source records attributed to Bellina, B..

3 recordsLinked to original sources

Sputum Proteomics reveals unique signatures linked to key outcomes in cystic fibrosis trials.

RationaleLung function (FEV1) and quality of life (QoL) are key outcomes in most interventional clinical trials conducted in people living with cystic fibrosis. However, no robust pre-clinical surrogates for FEV1 and QoL exist. The precise physiological mechanisms leading to treatment-related improvements in these outcomes are incompletely understood. In this post-hoc analysis we explored the relationship between changes in the sputum proteome and these outcomes with the aim of identifying translational biomarkers. MethodsPaired sputum samples collected during the AZTEC-CF study (NCT02894684) pre and post 14 days of antibiotic treatment for an acute pulmonary exacerbation were included. Samples were analysed using in vitro Mesoscale Discovery (MSD) assays and by nano LC-MS/MS. Peptide identification and quantification was performed and the log-fold change for individual proteins and relationships between protein change and changes in FEV1 and QoL were evaluated. ResultsDistinct patterns were found between proteins that correlated with FEV1 and those that correlated with QoL improvements. FEV1 improvement was characterised by increases in bacterially-derived proteins accompanied by decreases in proteins relating to neutrophil degranulation. Conversely, changes in QoL were associated with increases in antiprotease and antioxidant proteins. MSD analysis revealed changes in some neutrophil-associated markers significantly correlated with FEV1 improvements, but no markers significantly correlated with QoL improvements. ConclusionsThese results suggest changes in two key CF clinical trial outcomes (FEV1 and QoL) may be underpinned by different physiological mechanisms. Understanding these divergent mechanisms is vital to fortify optimal clinical trial design in CF and panels of biomarkers may be needed to improve translational confidence.

immunology↗

Native Mass Spectrometry Reveals the Conformational Diversity of the UVR8 Photoreceptor

UVR8 is a plant photoreceptor protein that regulates photomorphogenic and protective responses to UV light. The inactive, homodimeric state absorbs UV-B light resulting in dissociation into monomers, which are considered to be the active state and comprise a {beta}-propeller core domain and intrinsically disordered N- and C-terminal tails. The C-terminus is required for functional binding to signalling partner COP1. To date, however, structural studies have only been conducted with the core domain where the terminal tails have been truncated. Here, we report structural investigations of full-length UVR8 using native ion mobility mass spectrometry adapted for photo-activation. We show that, whilst truncated UVR8 photo-converts from a single conformation of dimers to a single monomer conformation, the full-length protein exist in numerous conformational families. The full-length dimer adopts both a compact state and an extended state where the C-terminus is primed for activation. In the monomer the extended C-terminus destabilises the core domain to produce highly extended yet stable conformations, which we propose are the fully active states that bind COP1. Our results reveal the conformational diversity of full-length UVR8. We also demonstrate the potential power of native mass spectrometry to probe functionally important structural dynamics of photoreceptor proteins throughout nature.\n\nTOC Graphic\n\nO_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=141 SRC=\"FIGDIR/small/371658_ufig1.gif\" ALT=\"Figure 1\">\nView larger version (60K):\norg.highwire.dtl.DTLVardef@177c6f9org.highwire.dtl.DTLVardef@a845c9org.highwire.dtl.DTLVardef@17db14forg.highwire.dtl.DTLVardef@103d4f8_HPS_FORMAT_FIGEXP M_FIG C_FIG

biochemistry↗

ORIGAMI: A Software Suite for Activated Ion Mobility Mass Spectrometry (aIM-MS) Applied To Multimeric Protein Assemblies

We present here a software suite (ORIGAMI) that facilitates the rapid acquisition and analysis of ion mobility data following collisional activation. ORIGAMI was developed for use on Waters Synapt instruments where data acquisition is achieved by interfacing WREnS (Waters Research Enabled Software) and MassLynx. Two components are presented, the first is ORIGAMIMS which enables activation of ions by sequential increase of collision voltages prior to ion mobility analysis. We demonstrate the use of ORIGAMI on the tetrameric assemblies formed by the proteins concanavalin A (103 kDa) and alcohol dehydrogenase (143 kDa). Activation is performed in the trap collision cell of the Synapt TriWave assembly, where the collision voltage can be ramped from 0-200 V. All of the acquired data is recorded in a single file which simplifies data acquisition. This substantially decreases the time needed to perform a typical activated IM-MS experiment on a single protein charge state from approx. 2 hours to ~25 minutes. Following data acquisition the data is analysed in the second component, ORIGAMIANALYSE, which allows the user to visualise the effect of activation on the mobility of the parent ion, as well as on any produced fragment ion. The user can export the data in the form of heat maps, waterfall or wire plots. In addition, tools implemented in ORIGAMI enable easy data extraction from single or multiple MassLynx .raw files, in-depth interrogation of large datasets, statistical analysis and figure creation capabilities. We demonstrate the use of ORIGAMI on concanavalin A and alcohol dehydrogenase acquired using the traditional protocols and the ORIGAMIMS method.\n\nHighlights- New methodology for faster acquisition and data analysis following activation of ions separated by ion mobility mass spectrometry\n- Software package capable of simultaneous analysis of multiple MassLynx .raw files\n- Visualization of the change in mobility of parent and fragment ions following activation\n- Easy extraction, data processing and extensive plotting tools

bioinformatics↗