White-gray-opaque transitions are independent of the MTL.

(A) Cellular morphologies of white, gray and opaque cells of BJ1097a (MTLa/Δ) and BJ1097α (MTLΔ/α). Scale bar, 10 µm. (B) White, gray, and opaque cells differ in mating efficiencies. Experimental strains with MTLΔ/α URA3⁺sat1⁻ (or Clon−) genotype: the wor1/wor1, efg1/efg1, wor1/wor1 efg1/efg1 double mutants, and the wild type BJ1097α. Tester strain WTa (MTLa/a, ura3⁻Clon+). Mating efficiency = average ± standard deviation (SD). The fold changes of mating efficiencies to that of WT white cells are also shown. The mean values were used for calculations.