Discovery and Development of Inhibitors that Selectively Interfere with Cyclin-Dependent Kinase Substrate Recognition
Abstract
The Origin Recognition Complex is thought to recognize Origins of Replication and recruit replication initiation factors in mammalian cells. The loading of this complex on DNA origins is required for replication in lower organisms, and it is thought that these proteins are important for replication control in higher eukaryotes. In this funding cycle, we show that Orc2 RNAi activates several mechanisms to arrest the cell cycle in G1 phase, preventing entry into S-phase without Orc2. We then studied a stable cell line expressing low levels of Orc2. As these cells are stable, they have escaped the requirement for Orc2, making them useful for examining the effects of low Orc2 on replication. We find that several ORC members are decreased in the absence of Orc2, and that other Orcs, as well as the pre-RC, are not properly loaded on chromatin. Despite this, the Orc2 hypomorph cells (which are p53-) don't show any additional origin firing ;defect when compared to p53-/- cells. The hypomorph cells replicate at the same rate, and even grow at the same rate as the p53 -/- cells, indicating that the absence of Orc2 has little, if any, effect on replication, despite extremely reduced pre-RC loading.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 2004
- Accession Number
- ADA430337
Entities
People
- Anindya Dutta
- Jamie Teer
Organizations
- Brigham and Women's Hospital