In: Biology
Describe how cdc2 kinase activity is controlled by interacting with Cyclin, cdc25, CAK and by phosprylation/dephosphorylation.
Answer: The mechanism of phosphorylation/dephosphorylation of cdc2 kinase (CDK) is given below in handwritten with typed explanation further:
CDK activity is first regulated by cyclin which changes cyclically. M-cyclin assembly with cdc 2 subunit of CDK leads to M-CDK complex formation which is kept inhibited by Wee1 (CDK inhibiting kinase) by phosphorylation at tyrosine 15 position of cdc2. CAK (CDK activating kinasr) then phosphorylated CDK (cdc2) at threonine 161 position but M-CDK remains inactive still due to inhibitory tyrosine 15 phosphate. This tyr15 phosphate is then removed by cdc25 by dephosphorylation and leads to activation of M-CDK.