Biochemical and genetic evidence supports Fyv6 as a second-step splicing factor in Saccharomyces cerevisiae

Genetic interactions between Fyv6 and Prp8, Prp16, or Prp22. (A) Diagram of how Prp8, Prp16, and Prp22 alleles impact the first and second steps of splicing. (B) Alleles of Prp8 were combined with fyv6Δ in Prp8 shuffle strains and grown on −Trp or −Trp + 5-FOA plates. Yeast growth was imaged after 3 d at 30°C. (C) Prp8^P986T/fyv6Δ strains were tested for suppression or exacerbation of temperature-dependent growth phenotypes. (D,E) Alleles of Prp16 and Prp22 were combined with fyv6Δ and tested for suppression or exacerbation of temperature-dependent growth phenotypes. For panels C–E, yeast were plated on YPD and imaged after 3 (30°C), 4 (23°C and 37°C), or 10 (16°C) days.