Figure 4.
Sequence alignment of apurinic/apyrimidinic endonuclease-like endonuclease (APE). Four Dualen elements and representatives of four groups of recently branched non-LTR retrotransposons, eukaryotic apurinic/apyrimidinic endonucleases (Drosophila melanogaster and Arabidopsis thaliana), and prokaryotic exonuclease III (Escherichia coli K12 and Synechocystis sp. PCC 6803) were aligned. Residues conserved among all sequences are red, and residues conserved among Dualen elements are yellow. Residues conserved among other retrotransposons, but not among Dualen elements, are green. Catalytic residues are indicated by asterisks.
