1. Proteins that regulate the cell cycle by binding to and activating cyclin-dependent kinases; their levels rise and fall during different phases of cell division.
Usage: biology; plural form of cyclin; technical term used in molecular and cell biology

Examples

• Cyclins control the progression of cells through the different stages of mitosis.
• The concentration of cyclins fluctuates throughout the cell cycle.
• Cyclin B is essential for the transition from G2 phase to mitosis.
• Mutations affecting cyclins can lead to uncontrolled cell division and cancer.
• Scientists study cyclins to understand how cells regulate their growth and division.