Cleavage of both LexA and UmuD is stimulated by a protein called RecA, which is activated by single-stranded DNA resulting from DNA damage.

TLS Online TPP Program

#Id: 8644

#Unit 2. Cellular Organization

Phosphorylation on multiple sites by G1 CDKs blocks Rb from associating with E2F and promotes its export out of the nucleus.

TLS Online TPP Program

#Id: 8645

#Unit 2. Cellular Organization

Rb protein regulation by G1 CDKs in mammalian cells is analogous to Whi5 regulation by Cln3-CDK in yeast.

TLS Online TPP Program

#Id: 8646

#Unit 2. Cellular Organization

One of the important substrates of the G1/S phase cyclin-CDK complexes is Cdh1.

TLS Online TPP Program

#Id: 8647

#Unit 2. Cellular Organization

TLS Online TPP Program

#Id: 8648

#Unit 2. Cellular Organization

During exit from mitosis and G1, 

Cdh1 is de-phosphorylated and APC/Ccdh1 is active.

TLS Online TPP Program

#Id: 8649

#Unit 2. Cellular Organization

During S phase and mitosis, 

Cdh1 is phosphorylated, Cdh1 dissociates from APC/C, and APC/C becomes inactive.