The β-clamp binding motifs. A. Schematic to show the relative positions and sequences of the β-clamp binding motifs in Pol II, Pol III, Pol IV and Pol V. Shown for comparison is the consensus β-binding motif as identified by Dalrymple and others (2001) . B. A more detailed schematic of Pol V showing the β-binding motif in relation to known domains. Domains: F – finger; P – palm, T – thumb, LF – little finger and CTD – C-terminal domain.