Which activity of a DNA polymerase is responsible for proofreading the newly synthesized DNA?
Proofreading: DNA polymerase adds a new base to the 3′ end of the growing, new strand. (The template has a G, and the polymerase incorrectly adds a T rather than a C to the new strand.) Polymerase detects that the bases are mispaired.
What is the function of DNA polymerase 1 in DNA synthesis?
Abstract. DNA polymerase I (pol I) processes RNA primers during lagging-strand synthesis and fills small gaps during DNA repair reactions. However, it is unclear how pol I and pol III work together during replication and repair or how extensive pol I processing of Okazaki fragments is in vivo .
How are new DNA strands synthesized?
DNA replication is semiconservative. Each strand in the double helix acts as a template for synthesis of a new, complementary strand. New DNA is made by enzymes called DNA polymerases, which require a template and a primer (starter) and synthesize DNA in the 5′ to 3′ direction.
What is the starting point for DNA synthesis?
A primer is a short nucleic acid sequence that provides a starting point for DNA synthesis. In living organisms, primers are short strands of RNA. A primer must be synthesized by an enzyme called primase, which is a type of RNA polymerase, before DNA replication can occur.