Replicative helicase activation

jambomber's version from 2015-05-07 15:19

Section 1

Question Answer
Where was CMG purified from?Drosophila egg extracts
How do AAA+ATPases work?One sub unit contributes Walker A and B motifs and the other the Arganine finger
How was head to head configuration est?Based on observation from archeal homologs and EM
Why was Mcm mechanism unclearexhibits similar levels of homology to both the SF3 helicases, which operate on ssDNA, and the E. coli RuvB homohexamer, a AAA+ protein that translocates on double stranded DNA
Where does rep fork stop in Fu and walter exp leading strand DNA synthesis stops approximately 20 nucleotides from the crosslink. Roadblock at 40
What evidence is there that MCMs seperate?only once Mcm copy in purified CMG
How was it shown that hexamers seperate single-molecule analysis of bacteriophage l DNA replicating in Xenopus egg extracts. tethered both ends of stretched DNA - only bidirectional if sperating.
What coformations of Mcm in solutiona planar notched-ring and a more abundant spiral lock-washer CMG exclusively a planar closed state with Cdc45 and GINS bridging the Mcm2-5 gap.
How s lagging strand displaced during unwinding?Cdc45 possesses homology to the catalytic domain of the prokaryotic RecJ exonuclease, RecJ-related domain could potentially bind the displaced lagging strand template during unwinding, Nuclease activity?
What development might prove helpful in future? recent devel- opment of a system to replicate origin-containing plas- mids using lysates of yeast cells

Section 2

Question Answer
What is the active kinase in DDK also known asCdc7
What is Cdc45 req forrequired for the progression of DNA replication forks
What does GINS stand for? What is special about itGo-Ichi-Ni-San, last replication factor conserved in all eukaryotes to be identified (
What is an an alt cool name for CMG‘‘unwindosome’
What is relationship between Cdcu7 and Dbf4acts in association with an essential regula- tory subunit called Dbf4
How was it shown that CDK important to rep?Mutants deficient inMajor S-phase cyclin Clb5 activate early but not later origins
What order do the two kinases work inCdc7 can complete its role in the absence of CDK activity, but the converse is not true
How was it shown that DDK induces a conformational change in helicase?Bob1 bypasser mutations which compensate for ∆cdc7 occur in Mcm5- the one mcm not targeted by phosphorylayion