Figure 4.

Sequence alignment of the THD domain of h4-1BBL and representatives of conventional TNFSF members. β Strands present in h4-1BBL are labeled. The residues that are forming hydrogen bond interactions with h4-1BB are shaded yellow for h4-1BBL and green for other conventional TNFSF members. The conserved hydrophobic residue (tyrosine) present in the DE loop of conventional members is highlighted with a blue box. The residues of the D and E strands of protomer B that are making contacts with h4-1BB are highlighted in the red box.