Figure 3.

Conserved H2AX variants. H2AX is highly conserved through evolution. Shown here is an amino acid sequence comparison between human, mouse, Xenopus and Drosophila. Identical amino acids are shown in dark boxes, and light boxes display blocks of similar amino acids. Light grey letters indicate nonsimilar amino acids, grey letters conserved and black letters weakly similar amino acids. The SQEY motif is underlined, and Serine 139, the residue that becomes phosphorylated upon induction of DSBs, is displayed in red. H2AX protein sequences were obtained from Swiss-Prot/TrEMBL and aligned using the VectorNTI software.