Lack of PEF1 increases the lysis rate in mutants with membrane merger defects. (A) Quantification of the lysis rate during germling fusion of the wild-type strain (FGSC 988) compared to ∆pef1 (FGSC 15890), ∆fig-1 (FGSC 17273), ∆lfd-1 (JPG6), ∆lfd-2 (FGSC 19267), and double mutants (GN8-76, GN10-10, GN8-80, respectively). (B) Quantification of the lysis rate during germling fusion of the wild-type strain (FGSC 988) compared to ∆pef1 (FGSC 15890), the double mutants ∆pef1/∆syt-1 (GN6-47) and ∆Prm1/∆syt-1 (GN6-42), and the triple mutant ∆Prm1/∆pef1/∆syt-1 (GN6-48). Strains were grown on MM or MM with 50% Ca2+. Error bars indicate the SD calculated from three independent experiments (n = 100 each). The asterisks represent statistically significant differences determined by the Student’s t-test (*P ≤ 0.05; ***P ≤ 0.001).