TABLE 2.

ess alleles suppress smk1 spore formation defects in a glucose-dependent manner

	YEPD/SPO-Da				YEPA/SPOb
26°		34°		26°		34°
Strain	Meiosisc (%)	Sporesd (%)	Meiosis (%)	Spores (%)	Meiosis (%)	Spores (%)	Meiosis (%)	Spores (%)
smk1-Δ ESS	68	0	46	0	73	0	65	0
SMK1 ESS	55	90	59	85	93	100	86	96
smk1-2 ESS	67	67	52	13	83	78	78	6
smk1-2 ess2	68	92	58	78	NAe	NA	NA	NA
smk1-2 ess64	65	82	63	88	86	75	81	10
smk1-2 ess67	52	85	75	85	91	85	86	9

^aStrains were pregrown on solid YEPD overnight, transferred to solid sporulation medium containing 0.05% glucose, and incubated at the smk1-2 permissive (26°) or nonpermissive (34°) temperature for 4 days. Subsequently, cells were fixed in ethanol, stained with the DNA-specific dye DAPI, and viewed by phase contrast/fluorescence microscopy. The strains were processed in parallel with the fluorescence assay shown in Figure 1 for comparison. At least 200 cells were viewed for each strain.

^bStrains were pregrown in liquid YEPA medium to early log phase, transferred to sporulation medium lacking glucose, and assayed as described above.

^cMeiosis was scored as the percentage of cells that contained multiple DAPI-stained foci.

^dSpore formation was scored as the percentage of cells that had completed meiosis and also exhibited spores under phase-contrast microscopy.

^eThe ess2 strain initiated sporulation precociously during pregrowth in YEPA and was therefore not assayed.