Cell Cycle Control and Cancer – Flashcards

Proteins produced in synchrony with the cell cycle and they combine with certain protein kinases (CDK).

They control the progression of cells through the cell cycle by activating CDK (cyclin dependent kinase) enzymes.

They are a group of protein kinase enzymes that control the progress through the cell-cycle. They are only active when complexed with cyclin.

They are the key driver of cell division in the cycle. They signal the cell by letting it know that it is ready to pass into the next stage of the cell cycle.

Cyclins bind to the CDKs, activating them to phosphorylate other molecules.

They allow the cell cycle to be delayed or paused when necessary. They are used to assess its internal state and integrate external signals.

The passage through the checkpoints are controlled by active and inactive CDK enzymes in the cell cycle.

It is the primary point where the cell decides to divide or not. It is also where external signals can influence events of the cycle. Growth factors affect the cycle and also the phase that links cell division to cell growth and nutrition.

It is the second cell-division control point, where division can be delayed if DNA hasn't been properly replicated or is damaged. -It is very complex and is important as the stimulus for the events of mitosis. -MPFs= Where CDKs are active -Passage through this checkpoint signals a commitment to mitosis.

It ensures that all of the chromosomes are attached to the spindle in preparation for anaphase. It is also important that they are arrayed at the metaphase plate.

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An unrestrained growth and division of cells; it results from a failure of cell division control.

It is a gene that produces the p53 protein that monitors DNA integrity and halts cell division of DNA damage is detected. -Many types of cancers are associated with a damaged or absent p53 gene. -If DNA is not able to be repaired, the p53 gene tells the cell to kill itself. Halting division of damaged cells. p53 prevents development of many mutated cells= Tumor suppressor gene

Normally functions to inhibit cell division; mutated forms can lead to the unrestrained cell division of cancer, but only when both copies of the gene are mutant. -If the p53 protein is abnormal, then it fails to stop cell division and to repair DNA. The cell then divides without repair to damaged DNA(mutation). These cells continue to divide, if more damage(mutation) occurs the cell can turn cancerous.