Interplay of EXO70 and MLO proteins modulates trichome cell wall composition and susceptibility to powdery mildew

0587334 - ÚEB 2025 RIV US eng J - Článek v odborném periodiku
Huebbers, J. W. - Caldarescu, G. A. - Kubátová, Z. - Sabol, P. - Levecque, S. C. J. - Kuhn, H. - Kulich, I. - Reinstaedler, A. - Büttgen, K. - Manga-Robles, A. - Melida, H. - Pauly, M. - Panstruga, R. - Žárský, Viktor
Interplay of EXO70 and MLO proteins modulates trichome cell wall composition and susceptibility to powdery mildew.
Plant Cell. Roč. 36, č. 4 (2023), s. 1007-1035. ISSN 1040-4651. E-ISSN 1532-298X
Grant CEP: GA MŠMT(CZ) EF16_019/0000738; GA MŠMT(CZ) LM2023050
Institucionální podpora: RVO:61389030
Klíčová slova: mediated disease resistance * exocyst subunit exo70h4 * callose synthase * plasma-membrane * arabidopsis trichomes * defense * complex * family * gene * secretion
Obor OECD: Cell biology
Impakt faktor: 12.0, rok: 2022
Způsob publikování: Open access
https://doi.org/10.1093/plcell/koad319

Exocyst component of 70-kDa (EXO70) proteins are constituents of the exocyst complex implicated in vesicle tethering during exocytosis. MILDEW RESISTANCE LOCUS O (MLO) proteins are plant-specific calcium channels and some MLO isoforms enable fungal powdery mildew pathogenesis. We here detected an unexpected phenotypic overlap of Arabidopsis thaliana exo70H4 and mlo2 mlo6 mlo12 triple mutant plants regarding the biogenesis of leaf trichome secondary cell walls. Biochemical and Fourier transform infrared spectroscopic analyses corroborated deficiencies in the composition of trichome cell walls in these mutants. Transgenic lines expressing fluorophore-tagged EXO70H4 and MLO exhibited extensive colocalization of these proteins. Furthermore, mCherry-EXO70H4 mislocalized in trichomes of the mlo triple mutant and, vice versa, MLO6-GFP mislocalized in trichomes of the exo70H4 mutant. Expression of GFP-marked PMR4 callose synthase, a known cargo of EXO70H4-dependent exocytosis, revealed reduced cell wall delivery of GFP-PMR4 in trichomes of mlo triple mutant plants. In vivo protein-protein interaction assays in plant and yeast cells uncovered isoform-preferential interactions between EXO70.2 subfamily members and MLO proteins. Finally, exo70H4 and mlo6 mutants, when combined, showed synergistically enhanced resistance to powdery mildew attack. Taken together, our data point to an isoform-specific interplay of EXO70 and MLO proteins in the modulation of trichome cell wall biogenesis and powdery mildew susceptibility.
Trvalý link: https://hdl.handle.net/11104/0354569