1. Sliding clamps: A (tail)ored fit
Manju M. Hingorani, Mike O’Donnell 
Current Biology 
Volume 10, Issue 1, Pages R25-R29 (January 2000)
DOI: /S (99)

2. Figure 1
Clamps, clamps everywhere… Front (left) and side (right) views of crystal structures of sliding clamps from bacteriophage T4 (gp45), bacteriophage RB69, E. coli (β), S. cerevisiae (yPCNA) and humans (hPCNA).
Current Biology  , R25-R29DOI: ( /S (99) )

3. Figure 2
RB69 DNA polymerase, the RB69 clamp and PCNA. (a) A model structure of DNA polymerase with primer–template DNA in the editing site, docked with the sliding clamp. (b,c) The RB69 clamp and human PCNA are shown complexed with the carboxy-terminal peptides (red) of (b) RB69 DNA polymerase and (c) p21CIP1.
Current Biology  , R25-R29DOI: ( /S (99) )

4. Figure 3
Oh what a tangled web we create, when we begin to replicate. During coordinated leading-strand and lagging-strand replication, the leading DNA strand undergoes torsional stress as it cannot swivel freely behind the polymerase (1→2). If the leading polymerase transiently releases the primer–template, while remaining bound to the clamp (2→3), the DNA can swivel back, within the clamp, to its original configuration (3→1).
Current Biology  , R25-R29DOI: ( /S (99) )