CDK2, or Cyclin-Dependent Kinase 2, is an essential enzyme that plays a crucial role in regulating the cell cycle. It helps control the transition between different phases of the cell cycle, particularly the progression from the G1 phase to the S phase, where DNA replication occurs. CDK2 functions by forming complexes with specific proteins called cyclins, which activate its kinase activity. Dysregulation of CDK2 can lead to various diseases, including cancer, as it may cause uncontrolled cell division. Researchers study CDK2 to better understand its role in cell cycle regulation and to develop potential therapeutic strategies targeting cancer and other related conditions.