Nucleosome Assembly Protein 1, Nap1, Is Required for the Growth, Development, and Pathogenicity of Magnaporthe oryzae

Magnaporthe oryzae is the causal agent of rice blast, leading to significant reductions in rice and wheat productivity. Nap1 is a conserved protein in eukaryotes involved in diverse physiological processes, such as nucleosome assembly, histone shuttling between the nucleus and cytoplasm, transcriptional regulation, and the cell cycle. Here, we identified Nap1 and characterized its roles in fungal development and virulence in M. oryzae. MoNap1 is involved in aerial hyphal and conidiophore differentiation, sporulation, appressorium formation, plant penetration, and virulence. Delta Monap1 generated a small, elongated, and malformed appressorium with an abnormally organized septin ring on hydrophobic surfaces. Delta Monap1 was more sensitive to cell wall integrity stresses but more resistant to microtubule stresses. MoNap1 interacted with histones H(2)A and H2B and the B-type cyclin (Cyc1). Moreover, a nuclear export signal (NES) domain is necessary for Nap1's roles in the regulation of the growth and pathogenicity of M. oryzae. In summary, NAP1 is essential for the growth, appressorium formation, and pathogenicity of M. oryzae.

Automated summary

Studies have shown that Nap1 plays a crucial role in Magnaporthe oryzae, participating in regulating fungal development and virulence, especially in appressorium formation and plant penetration.