The spo20-KC104 mutant is defective
in sporulation. (A) Kinetics of meiosis in a wild-type (WT) and a
spo20-KC104 mutant. YN13–14
(h+/h-
spo20-KC104/spo20-KC104 ade6-M210/ade6-M216) and
YN49–53 (h+/h-
ade6-M210/ade6-M216) precultured overnight in liquid
growth medium (SSL+N) were incubated with shaking at 25°C in liquid
sporulation medium (SSL-N). A portion of the culture was stained with
DAPI. Meiotic cells were classified by the number of nuclei per cell.
For each sample, ∼500 cells were counted. This figure is depicted on
the basis of one representative result of four independent experiments
that provided similar results. Diamonds, mononucleate cells; circles,
binucleate zygotes; triangles, trinucleate or tetranucleate cells. (B)
DAPI image of spo20-KC104 during sporulation. YN10
(spo20-KC104) and YN12 (WT) were incubated at 25°C in
sporulation medium (MEA) for 24 h. Chromosomal DNA was stained
with DAPI. Bar, 10 μm.