Cardiolipin

an unusual “double” phospholipid containing four fatty acid chains

found primarily in the inner mitochondrial membrane

acts to improve the efficiency of oxidative phosphorylation, by restricting proton flow across the membrane

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

TLS Online TPP Program

#Id: 8619

#Unit 2. Cellular Organization

INK4s

bind to CDK4 and CDK6 monomers, blocking their interaction with cyclin D