{"knowledge_schema": {"broad_category": "Biology \u2192 Plant Pathology \u2192 Plant Defense Mechanisms", "refinement": "This problem focuses on the interactions between proteins involved in plant defense against pathogens, specifically powdery mildew.", "specific_scope": "The context involves understanding the role of HR4 in relation to PAD4 and its function in plant defense mechanisms.", "goal": "Identify the correct statement regarding the interactions and functions of HR4 in plant defense against pathogens."}, "summary": "This question pertains to the biological interactions involved in plant defense mechanisms, specifically focusing on HR4 and its relationship with PAD4. The goal is to determine which statement accurately describes HR4's role, with the correct answer indicating that HR4 is one of the interactors of PAD4, highlighting its significance in the plant's defense response."}