Chapter 12- Replication Flashcards
Each new DNA molecule has one parent strand and one daughter strand
Semiconservative replication
One new DNA molecule contains both parental strands, while the other contains both daughter strands
Conservative Replication
Each new strand contains interspersed parental and daughter segments
Dispersive Replication
A type of replication that occurs in E. coli and in many other bacteria with circular genomes, with a single origin of replication.
Theta Replication
A type of DNA replication that occurs in all eukaryotes, which have linear chromosomes, has multiple origins of replication.
Linear DNA Replication
The places where replication initiates. There is only one in theta replication, and many in linear replication.
Origins (Ori)
Replication from both sides of a replication bubble, in both theta and linear replication
Bi-directional Replication
A sequence of RNA nucleotides that DNA synthesis initiates with, in both theta and linear replication
RNA Primer
An enzyme that recognizes the RNA primer that catalyzes the addition of DNA nucleotides to the 3’ end of new strand, is driven by the template, and requires a free 3’-OH on the sugar, in both theta and linear replication
DNA Polymerase
The bond involving the 3’ OH of the newly synthesized strand and the 5’ PO4 of the next nucleotide, the formation of which is catalyzed by DNA Polymerase
Phosphodiester Bonds
The single origin of replication in E. coli
oriC
The initiator protein that binds to oriC in E. coli
DnaA
A protein that binds to the lagging strand, moves in the 5’ to 3’ direction, and breaks hydrogen bonds holding the two parent strands together
Helicase
A protein that stabilizes single-stranded regions during DNA replication
Single-strand binding proteins (SSBs)
A topoisomerase that relieves torsional strain in front of each fork
DNA gyrase
The specialized RNA polymerase that synthesizes RNA primers
Primase
The strand that is synthesized continuously in the same direction as fork progression
Leading Strand
The strand that is synthesized discontinuously, in the opposite direction to fork progression, in short segments
Lagging Strand
The short segments that are there during the creation of the lagging strand
Okazaki Fragments
The DNA polymerase that removes the RNA primers with 5’ to 3’ exonuclease activity in E. coli
DNA pol I
The enzyme that catalyzes the formation of a phosphodiester bond between adjacent DNA segments
DNA ligase
The 3’ to 5’ exonuclease activity of DNA polymerase I and DNA polymerase III
Proofreading
DNA sequences involved in termination of replication
Ter sites
The protein that binds to Ter sites and prevents the replication fork from proceeding in order to terminate replication in E. coli
Tus protein
The eukaryote version of DnaA, which binds to origins to initiate DNA replication
Origin-recognition complex (ORC)
The multiple origins of replication in yeast
Autonomously Replicating Sequences (ARS)
The phase of the cell cycle in which replication of nuclear DNA occurs in eukaryotes
S-phase
The factors that attach to each origin in order to license them for replication
Replication Licensing Factors
The protein that prevents relicensing of an origin of replication in eukaryotes once replication initiates
Geminin
Repetitive DNA sequences at the ends of linear chromosomes, with species-specific tandem-repeats and a 3’ overhang, made of constitutive heterochromatin
Telomeres
A ribonucleoprotein (made of protein and RNA) that aids in DNA replication at the telomeres
Telomerase
The reverse transcriptase of telomerase, that binds specifically to telomere sequences
TERT
the RNA scaffold of telomerase, that contains a sequence that is complementary to the telomeric tandem repeat
TERC (hTR)
The cell type that loses telomerase activity during normal aging
Differentiated Somatic Cells
The cell type that has high telomerase activity and can continue to replicate indefinitely
Undifferentiated Stem Cells
