Biochemical Investigation and Evolutionary Comparison of the Mechanism of the Initiation of DNA Replication in Eukaryotic Cells

Stillman, Bruce, Ouyang, Meng, Zali, Narges, Hane, Kimberly, Hossain, Manzar (March 2024) Biochemical Investigation and Evolutionary Comparison of the Mechanism of the Initiation of DNA Replication in Eukaryotic Cells. In: UNSPECIFIED.

Abstract

During the G1 phase of the cell division cycle licensing origins of DNAreplication occurs and is followed by initiation of DNA replication from these origins in a defined and inherited temporal order during S phase. The vast majority of knowledge about the mechanism and control of licensing and subsequent replication has emerged from studies using the S. cerevisiae system, in which about 400 origins are licensed in G1 phase. In the origin licensing step, multiple DNA replication machinery components, specifically Orc1-6, Cdc6, Cdt1 and Mcm2-7, recognize origins of replication throughout the genome and form a pre-replication complex (pre-RC). ORC and Cdc6 recruit the Cdt1-Mcm2-7 complex to load the Mcm2-7 proteins onto the DNA, forming head-to-head MCM hexameric dimers that stay in an inactive state. Once activated by Cyclindependent (CDK) and Cdc7-Dbf4 (DDK) protein kinases and the recruitment of helicase activation factors, the helicase activities of the two MCM hexamers unwinds the DNA, initiating the replication process. In contrast to S. cerevisiae, it is estimated that there are approximately 50,000 origins in the human genome. The transition from licensing to initiation is tightly regulated both spatially and temporally. Understanding the features of an origin that determine its location in the genome, as well as the control and timing of origin activation remains an intriguing question in many eukaryotic cells. To address these issues, an evolutionary approach using biochemistry, structural biology and whole genome analyses has enabled comparison of origin location in multiple species. In S. cerevisiae, origins are located by the binding of ORC to specific DNA sequences. In contrast, in many yeasts and in human cells, indeed in most eukaryotes, origin location appears to be DNA sequence independent. Understanding the location of ORC binding sites in the genomes of multiple yeasts and in human cells and identification of proteins that interact with ORC and Cdc6 have advanced understanding of the mechanism of licensing of DNA replication in eukaryotes. Research was funded by a grant from the National Institute of General Medical Sciences, the Goldring FamilyFoundation and Cold Spring Harbor Laboratory.

Item Type: Conference or Workshop Item (Paper)
Subjects: bioinformatics
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > DNA, RNA structure, function, modification > DNA replication
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > DNA, RNA structure, function, modification
bioinformatics > genomics and proteomics > genetics & nucleic acid processing
bioinformatics > genomics and proteomics
CSHL Authors:
Communities: CSHL labs > Stillman lab
SWORD Depositor: CSHL Elements
Highlight: Stillman, Bruce W.
Depositing User: CSHL Elements
Date: March 2024
Date Deposited: 03 Dec 2024 14:02
Last Modified: 03 Dec 2024 14:02
Related URLs:
URI: https://repository.cshl.edu/id/eprint/41753

Actions (login required)

Administrator's edit/view item Administrator's edit/view item