GENE 540 Study Guide - Midterm Guide: Origin Recognition Complex, Cdc6, Dna Replication Factor Cdt1
Document Summary
Orc (origin recognition complex) stabilizes the dna orc remains associated with dna during all phases of the cell cycle. When cdc6 and cdc1 binds to orc (these proteins are in their unphosphorylated form this is only form that will allow them to bind to orc) Step 1 : during exit from mitosis and early g1, when cdk activity is low, the mcm loading factors orc, cdc6, and cdt1 load the replicative helicase, the mcm complex, onto. Dna at replication origins: cdc6 and cdt1 can only bind to the orc when they are not phosphorylated; once cdc6 and cdt1 proteins have bound to orc, they can then recruit the helicase. Helicase becomes phosphorylated this causes it to turn on. Step 2 : activation of s-phase cdks and. Sld3 (depicted as green phosphorylation events prereplication complex proteins are phosphorylated by the s-phase cyclin-cdk and another kinase called ddk), to facilitate the loading of mcm helicase activators the.
