Phosphorylase Kinase from rabbit muscle is widely utilized in biochemical research to study enzyme regulation and signal transduction pathways. It plays a critical role in catalyzing the phosphorylation of glycogen phosphorylase, which is essential for glycogen breakdown. Researchers use this enzyme to investigate metabolic processes, particularly those related to energy metabolism and glycogen regulation. It is also employed in studies focusing on calcium-dependent signaling, as its activity is modulated by calcium ions. Additionally, Phosphorylase Kinase serves as a model enzyme for understanding protein kinase mechanisms and their role in cellular responses. Its application extends to drug discovery, where it helps in identifying potential inhibitors or activators for therapeutic purposes.