DNA Replication Flashcards
What is the Structure and What are the Components Present in DNA Polymerase III
What are the stages in the the Eukaryotic Cell Cycle and is there DNA replication in each of these cycles
Steps in the Eukaryotic Replication Cycle
ORC Protein Binds
CDC and Cdt1 bind and recruit MCM Helicase
pre-Replicative complex formed
S-Phase
CDKs break apart pre-RC and attract polymerases
PCNA
proliferating cell nuclear antigen analog to the Beta clamp in prokaryotes
RFC
replication protein C similar to clamp loading complex
RPA
equivalent of SSB
Pol Alpha Primase
Primase and Polymerase activity
no proofreading, low processivity
initiates replication and Okazaki fragment
Pol Delta
Primary Lagging Strand Polymerase
proofreading with high processivity (PCNA)
Pol Epsilon
Primary leading strand polymerase
proofreading, high processivity
DNA Polymerase B
Involved in DNA Repiar
no proofreading, low fidelity, low processivity
Describe the Model for Initiation of Replicaiton in E. Coli
What enzymes are used
DnaA bind to R and I sites
DNA wraps tightly around DnaA inducing strain and separating DUE region
Two DnaB helicase bind to and unwind the opened DUE facilitated by DnaC
DNA Pol III loads and releases DnaA
Describe How the Termination of DNA replicaiton works in E. Coli what is the role of topoisomerase IV
Replication forks move around chromosome until they reach fork trap where Tus proteins bind to Ter sites
when one replication fork meets a stalled fork it also stops
DNA topo IV breaks both strand of the duplex and allows the other duplex to pass through
Cytosine Structure
Uracil
What is the structure of Thymine?
What is the structure of adenine?
What is the structure of Guanine?
