Time-dependent trajectory averages for (a) the angle between the axes A and B of the TCRαβ EC domain and (b) minimal Cα-atom root-mean-square deviations (RSMDs) of the TCRαβ, CD3εγ, and CD3εδ EC domains as well as the transmembrane (TM) domain relative to the cryo-EM structure of the T cell receptor – CD3 complex (Dong et al., 2019). Each data point is an average over the simulation structures of the 120 trajectories at the indicated time point, with error bars representing the error of the mean for these 120 structures. Axis A of the TCRαβ EC domain connects the centres of mass of Cαβ and Vαβ, where Cαβ is the dimer of the constant domains Cα and Cβ, and Vαβ is the dimer of the variable domains Vα and Vβ. Axis B connects the centres of mass of the variable domains Vα and Vβ (see 3(b) for illustration). The EC domains here are taken to span the residues V26 to C227 of TCRα, residues G22 to C264 of TCRβ, residues Q33 to V118 of CD3ε, residues F22 to M92 of CD3δ, and residues S24 to M103 of CD3γ.