Figure 3.

Chromosome Recoiling Is Inefficient or Defective during Anaphase in Condensin Mutants

Condensin mutants (smc2-8; T3829 and ycg1-2; T3992) and wild-type control cells (T3790) with Pgal-CDC20 TetR-GFP tetOs (integrated at three loci as in Figure 1A) were treated with α factor at 25°C and then released into fresh medium at 35°C (restrictive temperature for smc2-8 and ycg1-2) and arrested at metaphase by Cdc20 depletion for 2.5 hr. Synchronous anaphase was then induced by re-expression of Cdc20 and GFP images were acquired every 4 s for 30 min, both at 35°C.

(A) GFP signals were tracked as in Figure 1A. Graphs show the CEN-CEN (red) and CEN-HIS (blue) distances (time 0: CEN-CEN distance reached 3 μm). Time required for HIS segregation is defined as the period from time 0 until the CEN-HIS distance became <1.8 μm in the bud. Movies S2–S4 and Figure S3B also concern these cells.

(B) The percentage of cells, in which HIS segregation (defined as in A) completed within the indicated time window. n = number of observed cells.

(C) The segregation speed of the HIS locus toward the bud (rate of CEN-HIS shortening) was measured in T3790 (wild-type control) and T3829 (smc2-8) cells as indicated in (A). Thick lines indicate mean values.