Fig. 1.

Purification of human AH2. (A) Schematic diagrams of human HARP and AH2. Unique features of HARP include the N-terminal RPA-binding motif as well as two conserved HARP domains, which are found in HARP proteins. AH2 has an HNH motif in its C-terminal region. The positions of the motifs in HARP and AH2 are indicated. (B) Comparison of the HNH motif in AH2 with those in the MnlI and colicin E9 (ColE9) nucleases. The sequences of the HNH motifs in AH2 from humans (Homo sapiens), mouse (Mus musculus), western clawed frog (Xenopus tropicalis), zebra finch (Taeniopygia guttata), and Asian rice (Oryza sativa) are shown. This figure shows that the key H-N-H residues are conserved among AH2 proteins. The HNH consensus is from ref. 26. (C) Polyacrylamide-SDS gel electrophoresis of purified FLAG-tagged human AH2.