Extended Data Figure 8. Structural similarity between DHRs and repeat protein families.

DHRs cluster separately from existing repeat proteins. DHRs are equally distributed between right-handed and left-handed repeats, as referred to the repeat handedness, in contrast to known alpha helical repeat proteins, which are mostly right-handed. This result indicates that the handedness observed in known families is not an intrinsic limitation of repeat proteins structures. Repeat handedness, as defined by Kobe and Kajava⁶, indicates the rotation of the main chain going from the N- to the C-terminal around the axis connecting the repeat centers of mass. The structural similarity tree was built using pairwise comparison as measured by TM-score.