The Final Steps in the Initiation of DNA Replication: Activation of the Pre-replication Complex
- ISBN-10
- 0496348442
- ISBN-13
- 9780496348442
- Pages
- 270
- Language
- English
- Published
- 2003
- Publisher
- Cornell University, May
- Author
- Sara Lea Sawyer
Description
Mcm10 has recently been implicated in the initiation of DNA replication in several model systems. I find that pre-replication complex (pre-RC) components can load onto ARS1 in an mcm10-ts mutant. However, Mcm10 plays a role in the activation of the pre-RC. Mcm10 physically interacts with Cdc45, and recruitment of Cdc45 to ARS1 is dependent on Mcm10 activity. I show that both Mcm10-1 and Cdc45 are destabilized in the mcm10-1 mutant, and interpret this to mean that Mcm10 is stabilizing Cdc45. The temperature sensitivity of mcm10-1 is suppressed by overexpression of either Mcm10-1 or Cdc45, indicating that the complex can be stabilized by overexpressing the individual components. Although Mcm10 is constitutively chromatin bound, I show that it functions at the time of origin activation, directly stabilizing Cdc45 for origin loading.
