The protein APLF (aprataxin and PNK-like factor or Xip1; ) is a nuclease involved in single-strand and double-strand DNA break repair []. It has endo- and exonuclease activities and contains a FHA (forkhead-associated) domain and zinc-finger-like CYR motifs []. APLF interacts with XRCC1 and XRCC4 via its FHA domain [, ].
The PBZ (PAR-binding zinc-finger) domain is a zinc-finger motif that can be found in humans APLF (aprataxin- and PNK-like forkhead association domain-containing protein) [, ]. The Znf is highly conserved both in primary sequence and in the spacing between the putative zinc coordinating residues and is configured CX5CX6HX5H. Many of the proteins containing the APLF-like Znf are involved in DNA strand break repair and/or contain domains implicated in DNA metabolism [].
