This superfamily includes domain D of the Tip20p subunit, Dsl1p vesicle tethering complex, whose three subunits are essential for trafficking from the Golgi apparatus to the ER. Two of the three subunits, Tip20p and Dsl1p, resemble known subunits of the exocyst complex, establishing a structural connection among several multi-subunit tethering complexes and implying that many of their subunits are derived from a common progenitor. The structure of Tip20p consists entirely of alpha-helices and intervening loops of variable length, organised into a series of helix bundle domains.

DOI:10.1038/nsmb.1548