(a) Diagram of the Ndc80 complex depicting the antibody epitopes used for the Delta analysis. (b) Representative image of a normal mitotic metaphase cell labeled with antibodies to the Hec1 CH domain and the Spc24 head domain. Scale bar = 1 μm. (c) Delta values (corrected for tilt28) of mean separation between Spc24 and the Hec1 CH domain (9G3 antibody) in synchronized control or Cdt1-depleted mitotic cells (9 hrs after S phase release), or in Rod-depleted cells (mitotic metaphase cells selected from an asynchronous population); n = 84, 47, and 54 kinetochore pairs respectively; (control vs. si-cdt1) p < 0.001, (control vs. si-rod) p=0.31 (not significant). (d). As in c except that Delta values of separation between Nsl1 (Mis12 complex subunit) and the Hec1 CH domain were determined; n = 74, 41, and 60 kinetochore pairs respectively; (control vs. si-cdt1) p < 0.001, (control vs. si-rod) p = 0.86 (not significant). (e) Scale model for the Cdt1-Hec1 Loop domain interaction.