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Ghezellou, P.

Publications and source records attributed to Ghezellou, P..

2 recordsLinked to original sources

Evaluation of deep and dynamic proteomic screening strategies at sub-50Hz scan rate and without automation.

Advances in ultra-fast mass analyzer technology and procedural automation have enabled proteomics screening at the throughput of hundreds of proteomes per day. However, these approaches often require expensive instrumentation upgrades and robotic automation that remain inaccessible to many research laboratories and core facilities. In this study we address the feasibility of scaling up proteomic screening capabilities with minimal upgrade cost by focusing on (a) strategies for non-automated high-throughput sample preparation from 96-well cell culture, (b) data acquisition on sub-50Hz scan speed hybrid and tribrid Orbitrap instruments and (c) data analysis strategies for label-free and labeled proteomic screening. We find that the 96-well format STrap, in combination with C18 plates, provides the most robust throughput for a non-automated sample preparation workflow. Furthermore, we show that for static proteomes, an isobaric tandem mass tag-based (TMT) multiplexing approach provides deeper and more precise proteome coverage whereas label-free data-independent acquisition (DIA) is more accurate, albeit with a reduced dynamic range and more missing values. Finally, we extend the optimized workflow to proteome turnover studies using pulsed stable isotope labeling by amino acids in cell culture (pSILAC), highlighting the key advantages and trade-offs of DIA and TMT data-dependent acquisition strategies for capturing protein translation. Together, these results provide a practical framework for designing high-throughput proteomics experiments that balance throughput, depth, and quantitative accuracy using existing instrumentation, without requiring major hardware upgrades or automation.

molecular biology↗

A key regulator with a MIF-like domain orchestrates cellular differentiation and virulence in the fungal pathogen Magnaporthe oryzae

MACROPHAGE MIGRATION INHIBITORY FACTOR (MIF) is a pleiotropic protein with chemotactic, pro-inflammatory, and growth-promoting activities first discovered in mammals. In parasites, MIF homologs are involved in immune evasion and pathogenesis. Here, we present the first comprehensive analysis of a MIF protein from the devastating plant pathogen Magnaporthe oryzae (Mo). The fungal genome encodes a single MIF protein (MoMIF1) that, unlike the human homolog, harbors multiple low-complexity regions (LCRs) and is unique to Ascomycota. Following infection, MoMIF1 is expressed in the biotrophic phase of the fungus, and is strongly down-regulated during subsequent necrotrophic growth in leaves and roots. We show that MoMIF1 is secreted during plant infection, affects the production of the mycotoxin tenuazonic acid and inhibits plant cell death. Our results show that MoMIF1 is a novel key regulator of fungal virulence that maintains the balance between biotrophy and necrotrophy during the different phases of fungal infection.

plant biology↗