What are CDC6 and CDT1?
CDC6 is an ATP binding protein and a member of the pre-replicative complex (pre-RC) together with the origin recognition complex (ORC), Cdt1 and the MCM complex (containing MCM2-7p). CDC6 assembles after ORC in an ATP dependent manner and is required for loading MCM proteins onto the DNA.
What is the function of ORC?
Abstract. The origin recognition complex (ORC), a heteromeric six-subunit protein, is a central component for eukaryotic DNA replication. The ORC binds to DNA at replication origin sites in an ATP-dependent manner and serves as a scaffold for the assembly of other key initiation factors.
What is the MCM complex?
The MCM complex controls the once per cell cycle DNA replication in eukaryotic cells. In a process known as DNA replication licensing, it primes chromatin for DNA replication by binding origins of DNA replication during the late M to early G1 phase of the cell cycle.
What is the function of Cdc6 during S phase?
Cdc6 is also required during S phase to allow Chk1 activation in response to replication fork inhibition, though ORC-dependent chromatin binding is not required for this function.
In which replication ORC is present?
ORC is a central component for eukaryotic DNA replication, and remains bound to chromatin at replication origins throughout the cell cycle. ORC directs DNA replication throughout the genome and is required for its initiation.
What is the role of ORC complex in pre RC formation?
ORC Functions in Pre-RC Formation. Binding of ORC to DNA specifies sites where initiation of replication will occur, and this process is ATP-dependent. Experimental data indicate that ATP binding by ORC, but not the ATP hydrolysis, is important for DNA binding by the ORC.
What sequence does DnaA bind to?
DNA binding sites can be thus defined as short DNA sequences (typically 4 to 30 base pairs long, but up to 200 bp for recombination sites) that are specifically bound by one or more DNA-binding proteins or protein complexes.
What is MCM in molecular biology?
The minichromosome maintenance protein complex (MCM) is a DNA helicase essential for genomic DNA replication. Eukaryotic MCM consists of six gene products, Mcm2–7, which form a heterohexamer.
Is MCM a helicase?
Abstract. The MCM (minichromosome maintenance) complex is a helicase which is essential for DNA replication. Recent results suggest that the MCM helicase is important for replication fork integrity, and may function as a target of the replication checkpoint.
Is CDC6 a cyclin?
The cyclin binding domain of CDC6 was mapped to an N-terminal Cy-motif that is similar to the cyclin binding regions in p21(WAF1/SDI1) and E2F-1.
During which stage does CDT1 and CDC6 recruit MCM helicase to the origin?
G1 phase
Origin licensing occurs during late M phase and early G1 phase, when the pre-replication complex (pre-RC) forms at the origin. The pre-RC includes Cdt1, Cdc6, and two hexamers of the Mcm2–7 helicase. Origin firing occurs at the onset of S phase.
What is meant by Replisome?
Definition. The replisome is a large protein complex that carries out DNA replication, starting at the replication origin. It contains several enzymatic activities, such as helicase, primase and DNA polymerase and creates a replication fork to duplicate both the leading and lagging strand.
What does DnaC stand for?
DNAC stands for Dynamic Network Access Control (software)
What is DnaC replication?
DNA Replication: Initiation in Bacteria The function of DnaB as a helicase is to unwind the parental duplex DNA so that it can be copied by the replication fork machinery. Helicase recruitment involves a physical interaction between DnaA and DnaB in the DnaB–DnaC complex.
How is Orc regulated during mitosis?
ORC is regulated in a cell-cycle dependent manner. It is sequentially assembled at the exit from anaphase of mitosis and disassembled as cells enter S phase (PubMed: 12909626, PubMed: 17716973 ).
What is mitosis and how does it work?
Mitosis is a cellular process that replicates chromosomes and produces two identical nuclei in preparation for cell division. Generally, mitosis is immediately followed by the equal division of the cell nuclei and other cell contents into two daughter cells. We all started as one cell.
What is another name for mitosis in biology?
Alternative Title: karyokinesis. Mitosis, a process of cell duplication, or reproduction, during which one cell gives rise to two genetically identical daughter cells. Strictly applied, the term mitosis is used to describe the duplication and distribution of chromosomes, the structures that carry the genetic information.
What are the components of the ORC complex?
Component of ORC, a complex composed of at least 6 subunits: ORC1, ORC2, ORC3, ORC4, ORC5 and ORC6. ORC is regulated in a cell-cycle dependent manner. It is sequentially assembled at the exit from anaphase of mitosis and disassembled as cells enter S phase (PubMed: 12909626, PubMed: 17716973 ).