The Cell Cycle And Cancer Flashcards
Temperature sensitive cell division cycle
Restrictive high temp
Gene product not functional
Cells may grow in size but accumulate at a specific stage in the cell cycle
Temperature sensitive cell division cycle
Permissive low temp
Gene product is functional
Cells in all stages of the cycle are present
Mutant strain is ok
Cyclin domain kinase binds to cyclin and the protein inside forms a
T loop
Partly active
To fully activate the cdk you
Phosphorylate the t loop
3 major checkpoints
Entry to cell cycle and proceed to a phase
Entry to mitosis
Trigger anaphase and proceed to cytokinesis
G1 phase what happens and what does it cause/trigger
DNA replication complex binds to chromosome
G1 Cdk complex expressed and phosphorylates the TF that regulates S-Cdk
Made at the end of g1 inactive until S by supressors
Phosphorylation by G1-Cdk on suppressor triggers activation
S phase what happens and what does it trigger
S-Cdk phosphorylates DNA replication complex
Replicated once to duplicate genome
Sister chromatids made
G2 phase what happens and what does it trigger
M-cdk complex synthesised in S phase
Inactive until DNA replication is complete
Until the end of G2
M phase what happens and what is triggered
M-Cdk activated
Which activates number of substrates
Anaphase promoting complex is activated
Which regulates the degradation of cohesin and m-Cdk
What is APC
E3 ligase which also regulates S- and M-cyclins
What does taxol cancer cell line do and where is it arrested
Stabilises micro tubules and prevents spindle destruction
Arrest at M phase
What does nocodazole do and where does it arrest
Binds to beta tubulin and inhibits spindle formation
Arrest at M phase
What does doxorubicine do and where does it arrest
Binds to DNA double stand
Also targets topoisomerase activity
Arrest at S phase
What is cancer
Genetic disease Monoclonal Unable to achieve apoptosis Uncontrollable cell cycle Self sufficient growth signals
Tumour suppressor gene
What is it
Acts as cell breaks
Recessive mutation that causes cancer
Loss of this gene causes cancer
