Mononucleosomes typically have 200 bp DNA. End-trimming reduces the length of DNA first to 165 bp and then generates core particles with 146 bp.

TLS Online TPP Program

#Id: 8613

#Unit 2. Cellular Organization

Threonine -160 phosphorylation is mediated by 

CDK-activating kinase (CAK)

TLS Online TPP Program

#Id: 8614

#Unit 2. Cellular Organization

Two inhibitory phosphorylations on CDK play a critical role in controlling CDK activity:

Y15

T14

TLS Online TPP Program

#Id: 8615

#Unit 2. Cellular Organization

Y15 & T14 are situated in the G-loop of the CDK, containing the consensus sequence GEGT14Y15GVV

TLS Online TPP Program

#Id: 8616

#Unit 2. Cellular Organization

Phosphorylation of T14 and Y15 in this G-loop

introduces negative charge that electrostatically interferes with the binding of ATP in the catalytic pocket.

TLS Online TPP Program

#Id: 8617

#Unit 2. Cellular Organization

Wee1 kinase Inhibits CDKs in all organisms

TLS Online TPP Program

#Id: 8618

#Unit 2. Cellular Organization

Cdc25 phosphatase Activates CDKs in fission yeast