Phosphatidylinositol 5-phosphate (PI5P) is a phospholipid that plays a crucial role in cellular signaling and membrane dynamics. It is derived from phosphatidylinositol and is involved in various cellular processes, including endocytosis and cytoskeletal organization. PI5P acts as a signaling molecule, influencing the activity of proteins that bind to it. In addition to its signaling functions, PI5P is important for maintaining cellular homeostasis. It can regulate the activity of enzymes and other proteins, impacting processes such as cell growth and survival. Understanding PI5P's role can provide insights into various biological functions and potential therapeutic targets for diseases.