Secreted effector involved in biotrophic colonization of plant cells (PubMed:19357089). Induces an early, basal defense response in susceptible rice, including rapid callose deposition and ROS production in leaves and calli (PubMed:29551940, PubMed:29931642). Promotes also sporulation and mycelia growth suggesting a role across the whole process of interaction, from the biotrophic phase to sporulation (PubMed:29551940). Secreted into the biotrophic interfacial complexes (BICs). Expression is highly up-regulated in invasive hyphae. Leads to a slight decrease in lesion numbers and lesion sizes after host leaves infection.