Biological function of a Velvet protein CgrVosA in Colletotrichum graminicola

Abstract:

[Background] Colletotrichum graminicola, one of the main pathogens infecting maize, causes serious economic losses and directly threatens the global food security every year. Velvet proteins are fungal unique proteins with conserved functions, playing a role in regulating the growth and development of fungi. [Objective] To study the biological functions of a Velvet protein CgrVosA identified from C.graminicola. [Methods] The CgrvosA-knockout mutant and complementary strain were constructed by homologous recombination. The vegetative growth, stress response, conidial yield, germination, and pathogenicity of the strains were determined and compared to reveal the functions of CgrVosA. [Results] CgrvosA encoded a 425-residue protein with a typical Velvet protein domain. Compared with the wild type, ΔCgrvosA exhibited slow growth, high sensitivity to NaCl and H₂O₂, enlarged oval conidia, and reduced yield and germination rate of oval conidia. [Conclusion] The Velvet protein CgrVosA is involved in the regulation of vegetative growth, response to hyperosmotic and oxidative stress, and oval conidial production and germination of C.graminicola.