Which enzyme synthesizes a short RNA primer at the beginning of each origin of replication?

Answer 1

DNA polymerase III can add nucleotides only to a chain of nucleotides that is already

paired with the parent strands. Hence, DNA polymerase

cannot link the first nucleotides in a newly synthesized

strand. Instead, another enzyme, an RNA polymerase

called primase, constructs an RNA primer, a sequence of

about 10 RNA nucleotides complementary to the parent

DNA template. DNA polymerase III recognizes the primer

and adds DNA nucleotides to it to construct the new DNA

strands. The RNA nucleotides in the primers are then replaced

by DNA nucleotides.

Answer 2

Primase is the enzyme responsible for synthesizing a short RNA primer at the beginning of each origin of replication during DNA replication in prokaryotes and eukaryotes. The RNA primer provides the starting point for DNA polymerase to begin DNA synthesis.