Phenotype rescue of spindle checkpoint mutants.

<p>A) Yeast cells carrying the non-essential chromosome loss reporter were plated on agar plates with low adenine supplementation. The relative increase in sectored colonies after two days of growth (sectored colonies/white colonies) is indicative of higher chromosome loss rate, which is a phenotype easily visible in cells lacking Bub1. In contrast, cells carrying the SCP gene have a loss rate that is not distinguishable from wild-type. * indicates statistical significance P<0.001. B) Yeast cells expressing the single-copy protein (SCP) at the BUB1 locus can grow on YPD plates with 30ug/mL benomyl even in the absence of Mad3, as assessed by a 10-fold spot dilution assay. YPD plate was imaged after 2 days. YPD plate containing benomyl was imaged after 3 days.