RNA Primer synthesis and Primer-dependent DNA Synthesis
DNA
polymerases are primer-dependent: they
require an existing 3' end to begin nucleotide
attachment. A short RNA Primer is synthesized
chemically from the template strand by an RNA
Primase. This provides the necessary 3'
end, which is then extended by a DNA Polymerase.
Figure © 2012 TA Brown, Introduction
to Genetics (1st ed.); additional
text © 2014 by Steven M. Carr