Figure 5.
Conservation of the catalytic residues in the PIWI domain of all human Argonaute proteins as determined by X-ray crystallography. The catalytic amino acids are in the side surface of the PIWI domain, close to the RNA-binding groove. Among all the human Argonaute paralogs, only AGO2 and AGO3 retain the catalytic amino acid tetrad D-E-D-H. (a) AGO1 (PDB code: 4KRE), (b) AGO2 (PDB code: 4W5N), (c) AGO3 (PDB code: 5VM9), (d) AGO4 (PDB code: 6OON). All the figure panels were prepared with the Protein Imager software [39].