After discussion with Xiao, I believe the tetramer hypothesis of TAZ-TEAD is not correct. Reasons:

1. There are two TAZ-TEAD binding modes in the structure, 5gn0. And one is similar to the canonical YAP-TEAD structure, albeit TAZ has shorter loop between the alpha helix and omega loop.
2. the CoIP result just shows that TAZ can form homodimer, which is induced by its coiled-coil segment. And such coiled-coil segament is far from the TEAD binding domain.