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Thines, E.

Publications and source records attributed to Thines, E..

3 recordsLinked to original sources

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↗

Hunting the plant surrender signal activating apoplexy in grapevines after Neofusicoccum parvum infection

O_LIApoplectic breakdown from Grapevines Trunk Diseases (GTDs) has become a serious challenge to viticulture in consequence to drought stress. We hypothesise that fungal aggressiveness is controlled by a chemical communication between host and colonising fungus. C_LIO_LIWe introduce the new concept of a "plant surrender signal" accumulating in host plants under stress and triggering aggressive behaviour of the strain Neofusicoccum parvum (Bt-67) causing Botryosphaeriaceae-related dieback in grapevines. C_LIO_LIUsing a cell-based experimental system (Vitis cells) and bioactivity-guided fractionation, we identify trans-ferulic acid, a monolignol precursor, as "surrender signal". We show that this signal specifically activates secretion of the fungal phytotoxin Fusicoccin A. We show further that this phytotoxin, mediated by 14-3-3 proteins, activates programmed cell death in Vitis cells. C_LIO_LIWe arrive at a model pinpointing the chemical communication driving apoplexy in Botryosphaeriaceae-Vitis interaction and define the channelling of phenylpropanoid pathway from the lignin precursor, trans-ferulic acid to the phytoalexin transresveratrol as target for future therapy. C_LI

cell biology↗

Native Electrospray-based Metabolomics Enables the Detection of Metal-binding Compounds

Metals are essential for the molecular machineries of life, and microbes have evolved a variety of small molecules to acquire, compete for, and utilize metals. Systematic methods for the discovery of metal-small molecule complexes from biological samples are limited. Here we describe a two-step native electrospray ionization mass spectrometry method, in which double-barrel post-column metal-infusion and pH adjustment is combined with ion identity molecular networking, a rule-based informatics workflow. This method can be used to identify metal-binding compounds in complex samples based on defined mass (m/z) offsets of ion features with the same chromatographic profiles. As this native metal metabolomics approach can be easily implemented on any liquid chromatography-based mass spectrometry system, this method has the potential to become a key strategy for elucidating and understanding the role of metal-binding molecules in biology.

biochemistry↗