8.A.190. The Allergen Asp F2-like Protein (Asp F2) Family
Verticillium dahliae, a notorious phytopathogenic fungus, causes vascular wilt diseases in many plant species (Guo et al. 2022). The melanized microsclerotia enable V. dahliae to survive for years in soil and are crucial for its disease cycle. The secretory protein, Deletion of VdASP F2 from V. dahliae affected the formation of microsclerotia under adverse environmental conditions. VdASP F2 is localized to the cell wall, and transmembrane ion channel protein VdTRP (see TC# 1.A.4.9.6 and 7) interacts with VdASP F2. The deletion mutant was analysed showing that VdTRP is required for microsclerotial production, but it is not essential for stress resistance, carbon utilization and pathogenicity. Some differentially expressed genes related to melanin synthesis and microsclerotial formation were downregulated in the VdTRP deletion mutants. Thus, VdASP F2 regulates the formation of melanized microsclerotia by interacting with VdTRP (Guo et al. 2022). This protein is homologous to the pH-regulated antigen PRA1 (see TC#s 2.A.5.1.15 and 2.A.5.1.22). The latter entry includes an Asp F2 homolog that functions in conjunction with a Zinc uptake transporter of the ZIP family as a zincophore, feeding Zn2+ into the transporter (see TC# 2.A.5.1.22).