Myt 1 is important in regulating the cell cycle through inactivating Cdks through the phosphorylation of both Tyr 15 and Thr 14 There are other enzymes that play roles in the inactivation of Cdks in the Wee 1 family that work in a variety of different organisms.

[8] Myt 1 plays an important role in inhibiting Cdk activity through phosphorylating Tyr 15 and Thr 14.

It is thought that the phosphorylation of Tyr 15 and Thr 14 interferes with the orientation of ATP phosphates which inhibits Cdk functioning.

[9] With Myt 1 inactivating Cdks by phosphorylating both Tyr 15 and Thr 14, there needs to be a method of dephosphorylating the sites so that the Cdk can become active once again.

Myt 1 and Wee 1 concentrations are high throughout most of the cell cycle to ensure the inactivation of Cdk 1.

Since almost all cyclin B1-Cdk 1 complexes are found in the cytoplasm, Myt 1 may be the most important inhibitory kinase for Cdk 1.

This regulatory system creates a switch where Cdk 1 can be turned on and off quickly and ensures that the process will still operate even if some part fails.