Protein kinase C (PKC) is a family of enzymes that play a crucial role in various cellular processes, including cell growth, differentiation, and apoptosis. PKC is activated by signals such as growth factors and hormones, which lead to its phosphorylation and subsequent activation. Once activated, PKC phosphorylates specific target proteins, influencing their activity and function. This process is essential for regulating numerous physiological functions, including immune responses and neurotransmitter release. Dysregulation of PKC activity has been linked to various diseases, including cancer and diabetes.