Primase

DNA primase is form of RNA polymerase and a product of the dnaG gene . Primase binds to the DNA helicase forming a complex called the primosome. Primase is activated by DNA helicase where it then synthesizes a short RNA primer approximately 11 ±1 nucleotides long, to which new nucleotides can be added by DNA polymerase. Primase is of key importance in DNA replication because no known DNA polymerases can initiate the synthesis of a DNA strand.

A primer is a short RNA segment that is complementary to a DNA segment, and is necessary to begin DNA replication.

Types

• dnaB
• dnaC