DNA Replication

#1. Helicase unwinds helix with help of a topoisomerase forming "negative supercoils" just ahead of it.

#2. SSB's (single-stranded binding proteins) bind to the unwound strands to prevent them from re-annealing.

#3. RNA primase forms RNA primers that bind to the DNA. These are attached by DNA polymerase that zips along in the 5' --> 3' direction (ALWAYS!). Continuous synthesis for the leading strand.

#4. The lagging strand's RNA primers are attached as Okazaki fragments. DNA polymerase zips along in LOOPS (discontinous synthesis) in order to form DNA in the 5' --> 3' direction (opposite that of the leading strand).

- the OVERALL direction of synthesis for the lagging strand, however, is 3' --> 5'

#5. DNA ligase covalently links the fragments.

TAA-DAAAAAAA!!!!!!! DNA HAS DONE IT AGAIN.