RNA Primase, DNA polymerase III, Nucleoside Triphosphates

What does RNA primase do?

Builds short complimentary segments of RNA nucleotides (10-60) on the template strand

What is each segment called and how is it synthesized?

It is called a primer, and it is synthesized in the 3’ to 5’ direction (but it is 5’ to 3’ itself)

How does RNA primase help DNA Polymerase III?

It helps DNA Polymerase III find a point to build off from

What is Similar between RNA primase and DNA polymerase III?

Their nucleotides can only be built in the 3’ to 5’ direction

What does DNA polymerase III add starting at the end of RNA primers?

Nucleotides (Nucleoside triphosphates)

What is the difference b/w the Lagging strand and Leading strand when it comes to DNA polymerase III?

Leading strand only requires one because DNA is synthesized in the same direction as the movement of the replication fork (Helicase moving), while The lagging strand requires many because the DNA is synthesized in the opposite direction of the replication fork, so it is built in discontinuous segments away from the fork

What are Nucleoside Triphosphates?

They are similar to typical DNA nucleotides but they have 3 Phosphates

What is special about the 3 phosphates?

It gives them similar energy storage abilities to ATP

What is the purpose of the 3 phosphates for Nucleoside Triphosphates?

DNA Pol. III requires energy to synthesize DNA, so when 2 Phosphates in each nucleoside triphosphate hydrolyse, energy for DNA Pol. III to catalyze the synthesis reaction that adds a DNA nucleotide to the newly formed strand is released