Pre-replication complex

Nasmyth If you reactivated the kinase, given that the kinase inhibits prereplication complex formation, this would do the job. There are two ways of preventing replication one is not to make the components of the pre-replication complex, the other is to keep the kinase high, which inhibits that formation. This could be an explanation of the Nenopus work. 

Nasmyth We know that in G2, where HI kinase is not high, we know that there is sufficient cdk activity to inhibit pre-replication complex formation. If it has gone down at interphase, there still could be a lot of cdk present. 

Gautier As far as the pre-replication complex is concerned, just looking at the level of Cdc6/Cdcl 8 is not going to tell us anything, because in Nenopus eggs all the maternal protein is already made for 10 divisions. 

The pre-replication complex (pre-RC) is formed diming anaphase and is inherited by the sister chromatids. Upon entry into S phase, the pre-RC must be disrupted for initiation to occur. If initiation begins, the pre-RC changes to the post-rephcation complex state, which does not permit further initiation. 

Control of origin activity occurs via specific protein complexes that are bound at certain times of the cell cycle to a replication origin. For replication initiation, two states of this protein complex are important, known as the pre-replication complex and the post-replication complex (Fig. 13.17). 

DNA replication Is Initiated from pre-replication complexes assembled at origins during early Gi. S-phase cyclln-CDK complexes simultaneously trigger Initiation from pre-replication complexes and Inhibit assembly of new pre-replication complexes by phosphorylating components of the pre-replication complex (see Figure 21-26). 

Once cyclin A-CDK2 is activated by Cdc25A and the S-phase inhibitors have been degraded, DNA replication is initiated at pre-replication complexes. The general mechanism is thought to parallel that in S. cerevisiae (see Figure... 

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