Figure 1
From: Direct visualization of DNA baton pass between replication factors bound to PCNA
Reaction scheme of PCNA-mediated Okazaki fragment maturation (a–c) The sequential model. (a) Upon meeting the downstream fragment, DNA polymerase (PolB) displaces the primer region (indicated by bold dashed lines), to produce a flap DNA structure. (b) Next, FEN recognizes and cleaves the flap. (c) Finally, the nick is sealed by DNA ligase (Lig). (d) The standard tool belt model, in which all three of the enzymes are bound to a single PCNA trimer, and the three steps reactions are performed in order by the switching of these enzymes.
