FIGURE 2.
Dimerization of the BTN3A molecules in the crystal lattice. Two potentially physiologically relevant dimerization states were noted in the crystal lattices of each BTN3A isoform. BTN3A1 is shown as the representative. Top panel, BTN3A1 is in rainbow colors from the N terminus to the C terminus to clarify domain orientation of the two dimerization states. The Dimer 1 contact surface is symmetric via the A and G β-strands of the C domains of BTN3A, whereas the Dimer 2 contact surface is asymmetric, via a head-to-tail orientation via the C, C′, and C″ β-strands of the V domain with the A and D β-strands of the C domain. Middle panel, both dimers are shown as surface representations, with the dimerization interface color-coded in hot pink. The BSA in Å2 is indicated next to both dimer forms. Bottom panel, a cartoon representation of how these dimers would exist on the cell surface based on the location of the C-terminal transmembrane domains.