What controls the mitotic cell cycle?

The mitotic cell cycle is controlled by a complex system of proteins and enzymes, including cyclins and cyclin-dependent kinases.

The mitotic cell cycle, which is the process by which a single cell divides into two identical daughter cells, is a highly regulated process. This regulation is crucial to ensure that cell division occurs at the right time and in the right place. The key players in this regulation are a group of proteins and enzymes, including cyclins and cyclin-dependent kinases (CDKs).

Cyclins are proteins that control the progression of cells through the cell cycle by activating CDKs. The levels of cyclins within the cell rise and fall in tune with the cell cycle, hence their name. When cyclin levels are high, they bind to CDKs, activating them and allowing the cell to progress to the next stage of the cell cycle. When cyclin levels fall, the CDKs are deactivated, and the cell cycle is halted.

CDKs are enzymes that modify other proteins by adding phosphate groups to them, a process known as phosphorylation. When activated by cyclins, CDKs phosphorylate specific target proteins that are involved in controlling the cell cycle. This phosphorylation changes the activity of the target proteins, allowing the cell to progress through the cell cycle.

In addition to cyclins and CDKs, there are also several other proteins and enzymes involved in controlling the cell cycle. These include proteins that monitor the cell's environment and internal state to ensure that conditions are right for cell division, as well as proteins that repair DNA damage and prevent the cell from dividing if its DNA is damaged.

In summary, the mitotic cell cycle is controlled by a complex system of proteins and enzymes that work together to ensure that cell division occurs at the right time and in the right place. This system is crucial for maintaining the health and integrity of the organism.