XB-ART-17555Cell October 18, 1996; 87 (2): 287-96.
Interaction between the origin recognition complex and the replication licensing system in Xenopus.
The origin recognition complex (ORC) binds to origins of replication in budding yeast. We have cloned a Xenopus homolog of the largest ORC polypeptide (XORC1). Immunodepletion of XOrc1 from Xenopus egg extracts blocks the initiation of DNA replication. We have purified Xenopus ORC, consisting of a protein complex similar to yeast ORC. In Xenopus egg extracts, ORC associates with chromatin throughout G1 and S phases. RLF-M, a component of the replication licensing system, also associates with chromatin early in the cell cycle but dissociates during S phase. We show that the assembly of RLF-M onto chromatin is dependent on the presence of chromatin-bound ORC, leading to sequential assembly of initiation proteins onto replication origins during the cell cycle.
PubMed ID: 8861912
Article link: Cell
Species referenced: Xenopus
Genes referenced: orc1 rlf
Antibodies: Orc1 Ab1