Roles for the Conserved Spc105p/Kre28p Complex in Kinetochore-Microtubule Binding and the Spindle Assembly Checkpoint
Figure 3
Budding yeast Spc105p binds to microtubules and is required for sister chromatid bi-orientation.
(A) Affinity-purified Spc105p (Ssa1p is a co-purifying chaperon) binds to taxol-stabilized bovine MTs with a Kd of ∼1.2 µM as measured in MT-spindown experiments. (B) Loss of Spc105p/Kre28p activity increases the frequency of mono-oriented sister chromatids. In the microscopic image, the left spc105 cell shows a mono-oriented sister chromatid 3 pair (green dots), while in the right cell, the sister chromatid 3 pair is bi-oriented on the spindle. Position of the spindle is indicated by the two spindle pole bodies colored red.