The SNARE protein FolVam7 mediates intracellular trafficking to regulate conidiogenesis and pathogenicity in Fusarium oxysporum f. sp. lycopersici

Abstract

SummarySoluble N‐ethylmaleimide‐sensitive factor attachment protein receptors (SNAREs) are conserved in fungi, plants and animals. The Vam7 gene encodes a v‐SNARE protein that involved in vesicle trafficking in fungi. Here, we identified and characterized the function of FolVam7, a homologue of the yeast SNARE protein Vam7p in Fusarium oxysporum f. sp. lycopersici (Fol), a fungal pathogen of tomato. FolVam7 contains SNARE and PX (Phox homology) domains that are indispensable for normal localization and function of FolVam7. Targeted gene deletion showed that FolVam7‐mediated vesicle trafficking is important for vegetative growth, asexual development, conidial morphology and plant infection. Further cytological examinations revealed that FolVam7 is localized to vesicles and vacuole membranes in the hyphae stage. Moreover, the ΔFolvam7 mutant is insensitive to salt and osmotic stresses and hypersensitive to cell wall stressors. Taken together, our results suggested that FolVam7‐mediated vesicle trafficking promotes vegetative growth, conidiogenesis and pathogenicity of Fol.

FolVps9, a Guanine Nucleotide Exchange Factor for FolVps21, Is Essential for Fungal Development and Pathogenicity in Fusarium oxysporum f. sp. lycopersici

“…lycopersici ( Fol ) strain 4287 and mutant strains used in this study are listed in Supplementary Table S1. Vegetative growth rate was determined using potato dextrose agar (PDA) and complete medium (CM) at 28°C for 5 days (Li et al, 2019b). Conidiation was assayed as previously reported (Li et al, 2019b).…”

“…Vegetative growth rate was determined using potato dextrose agar (PDA) and complete medium (CM) at 28°C for 5 days (Li et al, 2019b). Conidiation was assayed as previously reported (Li et al, 2019b). The conidial morphology of wild type and mutants was examined using a Zeiss LSM 710 confocal microscope with a 63/1.2 NA C-Apochromat oil immersion objective (Zeiss, Oberkochen, Germany).…”

“…Pathogenicity experiments were performed three times with similar results. Fungal recovery assays were performed as previously described (Fradin et al, 2009; Li et al, 2019b). Root vascular bundles were observed using a Hitachi TM-1000 tabletop microscope.…”

“…Endocytosis is a conserved transport process in which macromolecules, lipids, or membrane proteins are transported to endosomal compartments. Recently, a series of studies have shown that endocytosis plays an important role in cell polarity, signal transduction and plant infection in phytopathogens (Wedlich-Soldner et al, 2000; Ramanujam et al, 2013; Li L. et al, 2017; Li et al, 2019b). During endocytosis, cargo is packaged by an area of plasma membrane, which then buds off inside the cell to form transport vesicles (Balderhaar and Ungermann, 2013; Li X. et al, 2017).…”

“…Fusarium oxysporum f.sp. lycppersici ( Fol ) is a soil-borne vascular fungal pathogen, which causes wilting disease or root rot on more than 100 different plants, including tomato, cotton, banana, melons and peppers (Michielse and Rep, 2009; Ouyang et al, 2014; Gonzalez-Cendales et al, 2016; Li et al, 2019b). Based on host specificity, F. oxysporum has been grouped into forma speciales (f.sp.)…”