Figure 5.

Meiotic segregation is defective in the RNAi mutants. (A) Segregation of cen1-GFP through meiosis. Strains were sporulated and subjected to fluorescent microscopy for cen1-GFP and differential interference contrast microscopy. Class I represents normal meiotic segregation, where each spore receives one copy of chromosome I. Class II represents a missegregation event during one of the two second meiotic divisions. Class III is caused by missegregation during both of the second meiotic divisions. Class IV is caused by missegregation of a single cen1-GFP chromatid during the first meiotic division. (Right) The frequency with which the respective phenotypic classes were observed. Only tetrads with four visible GFP spots were scored. More than 100 tetrads were counted for each genotype. Note different scales along the y axis. (B) Aberrant meiotic segregation as visualized by DAPI staining.