Clustal W alignment of the R391 Jef, CTnDOT Orf2c, and Gifsy-1 Xis. A residue ruler is indicated along the top of the figure. The ruler corresponds to the residue number of the Gifsy-1 Xis protein. The residue number for individual proteins is indicated on the left-hand side of the figure. The boxed sequences indicate the region of homology shared by the three proteins.