A multi-scale model of the yeast mitotic machinery in vivo. (A) The top half shows the types of Dam1C/DASH outer-kinetochore assemblies; left to right: partial rings, complete rings, complete ring without bridges, and complete ring with 17 bridges. The bottom half shows the possible position and tilt relationships between the Dam1C/DASH rings and the kMT plus end tips. The percent of each species observed in vivo is indicated. (B) Cartoon of clusters of Dam1C/DASH rings, viewed along the spindle axis. Dam1C/DASH (green) can only form complete rings when attached to kMTs (magenta). In the presence of attachment with or without tension, most of the rings are partial. (C) Inset: cartoon of a single Dam1C/DASH-kinetochore attachment site. The boxed area is enlarged, showing a schematic of Dam1C/DASH in cross section (green) and tubulin dimers (magenta rounded rectangles). The bridge is stably engaged with the MT wall (1) until the peeling protofilament becomes locally curved enough to destabilize the bridge’s interaction (2). If enough Dam1C/DASH bridges are freed, the ring can locally diffuse along the kMT axis until it encounters a wall the MT (3). Here the bridge makes a stable contact again, attaching Dam1C/DASH to a position closer to the minus end (4).