Actin-depolymerizing protein. Severs actin filaments (F-actin) and binds to actin monomers (By similarity). Involved in innate immunity. Required for the expression of defense-related genes PR1A, LOX2 and CHS1 upon biotic stresses. Required for basal resistance to the fungal blast (Magnaporthe grisea), bacterial blight (Xanthomonas oryzae pv. oryzae, Xoo) and the herbivorous insect brown planthopper (Nilaparvata lugens, BPH). Involved in the promotion of seed germination. Required for the expression of alpha-amylase genes during seed germination (PubMed:24033867). Interacts with LECRK1 (via kinase domain). Decreased germination rates due to decreased alpha-amylase activity during seed germination. Increased susceptibility to infection by the fungal blast (Magnaporthe grisea), bacterial blight (Xanthomonas oryzae pv. oryzae, Xoo) and the herbivorous insect brown planthopper (Nilaparvata lugens, BPH). Almost no induction of the defense-related genes PR1A, LOX2 and CHS1 after exposure to biotic stresses. Belongs to the actin-binding proteins ADF family.