Chapter 11 Flashcards
3 DNA sequences found within oriC
AT rich region, DnaA box sequences, and GATC methylation sites
Beginning of DNA replication
The binding of DnaA proteins to sequences within the origin of replication known as DnaA boxes
DnaA binds to 5 DnaA boxes in oriC to initiate DNA replication and to each other to form a complex
HU and IHF cause DNA to bend around the complex of DNAA proteins
RNA primers
The strand of RNA or synthesized by the main cage of ribonuclease via enzyme known as primase
Primase: synthesizes short strands of RNA, typically 10-12 nucleotides in length, which starts DNA replication
Leading strand
Single primer is made at the origin of replication
Lagging strand
Multiple primaries are made at the origin of replication
DNA polymerase
Is responsible for synthesizing the DNA along the leading and lagging strands
Catalyzes the formation of covalent bonds between adjacent nucleotides and there by makes the new daughter strands
Termination utilization substance (Tus)
A protein that binds to the ter
sequences and stops the movement of replication forks
Only one TER sequence is required to stop the advancement of replication fork, and then the other fork ends it’s synthesis of DNA when it reaches the haulted fork
Proofreading function
The ability to remove mismatched nucleotides, by exonuclease cleavage of the bonds between adjacent nucleotides at the 3’ end of the newly made strand
After mismatched nucleotide is removed, DNA polymerase resumes DNA synthesis in the 5’ to 3’ direction
ARS elements
Autonomously replicating sequences Are necessary to initiate Chromosome replication. Are about 50 bp in length
Initiated DNA replication in conjunction with primase
Polymerase type: α
Replication of leading strand
Polymerase Type: ε
Replication of lagging strand
Polymerase Types: δ
Replication of mitochondrial DNA
Polymerase type: γ
Flap endonuclease
Remove small RNA flaps that are generated by the action of DNA polymerase δ
