Figure 4.

Spo20 is a functional homologue of Sec14. (A) Overexpression of S. pombe spo20⁺ suppressed S. cerevisiae sec14–1^ts. A multicopy plasmid carrying spo20⁺ (pYESspo20) was transformed into an S. cerevisiae sec14–1^ts mutant. The Ura⁺ transformants were incubated in YP-Glucose and YP-Galactose for 3 d at 25 or 37°C. (B) Overexpression of S. cerevisiae SEC14 suppressed the temperature sensitivity of spo20-KC104. Strain YN11 (spo20-KC104) was transformed with an empty pREP1, pREP1SEC14, or pREP1spo20. The Leu⁺ transformants were incubated in complete medium (YEA) at 25 or 37°C for 5 d. (C) Suppression of sporulation defect in spo20-KC104 by S. cerevisiae SEC14. The Leu⁺ transformants with pREP1, pREP1SEC14, or pREP1spo20 were incubated in sporulation medium (MEA) at 25°C for 2 d. Bar, 10 μm. (D) Sporulation efficiency of the transformants. The Leu⁺ transformants with an empty pREP1, pREP1SEC14, or pREP1spo20 were incubated in MEA at 25°C for 2 d. (E) Viability of spores produced by SEC14-driven sporulation. A homozygous diploid carrying pREP1SEC14 was sporulated, and the dissected tetrads were incubated on complete medium (YEA) at 25°C for 5 d.