Fig. 1

Spatio-temporal coordination dynamics of Cx43 HC-HC reveal the build-up of trans-GJ SCs as an indicator for HC docking. A Large-scale side view of two membrane embedded Cx43 HCs, homology modelled using the calcium-free Cx31.3HC template (PDB code: 6L3T; SI Table S1) [66] (Cx43 HC-HC). Residues 55N-56T-57Q of pre- and post-GJ subunits A-J, B-I, C-H, D-G, E-L and F-K are highlighted light- and dark purple, grey, red, brown, green and blue, respectively. B Close view of the interface residues 55N-56T-57Q of the Cx43 HC-HC model show gradual disintegration of the trans-GJ interface with increasing distance between HCs. C After moving HCs away to 3 Å distance, appearance of specific trans-GJ SCs during 100 ns MD simulation show rebuilding of trans-GJ SC interactions. SCs defined at the A-J, B-I, C-H, D-G, E-L and F-K interfaces are highlighted in purple, grey, red, brown, green and blue, respectively. Trans-GJ SC pairs are designated as subunit name + residue number + 1-letter residue name. D Dynamics of trans-GJ SCs during the 100 ns MD simulation after moving HCs away to 3 Å distance demonstrate rebuilding of trans-GJ interactions. Note the development of trans-GJ SCs between subunit pairs C-H (light and dark red in C). E Residues forming trans-GJ SCs in top view of the Cx43 HC-HC models in the last 10 ns of MD simulations. Blue: 55N, red: 56T, green: 57Q, purple: 194H, orange: 195Q, violet: 196V