When DNA replicates, the enzyme helicase separates the DNA strands. Single-stranded DNA binding proteins then stabilize the unwound template DNA, keeping it in an extended single-stranded state so that it can be copied by DNA polymerase. One new DNA strand is called the leading strand, which forms from its 5′ to its 3′ end by the action of DNA polymerase III. A sliding-clamp forms a ring around the DNA and maintains the association of the DNA and the polymerase, allowing the uninterrupted synthe