rtn1Δ yop1Δ triple mutants showing no enhanced growth defects included nup84Δ, nup133Δ, nup145ΔN, snl1Δ, nup53Δ, nup170Δ, nup59Δ, brr6Δ/brr6-1, apq12Δ, nup57-E17, nup159-1/rat7-1, nic96-1, nup1Δ, nup2Δ, nup60Δ, nup42Δ, and nup100Δ. Synthetic lethal and synthetic sick strains were maintained with a URA3/CEN plasmid carrying wild-type copies of NUP85, NUP120, NUP145, POM34, NUP116, GLE2, or NUP188 or a wild-type copy of RTN1 for spo7Δ, nem1Δ, and nup82-3 triple mutants. Synthetic lethality indicates failure to grow on 5-FOA; synthetic sickness indicates moderate to severe growth inhibition on 5-FOA. Enhanced lethality indicates increased temperature sensitivity of 5-FOA–resistant ura⁻ isolates grown on YPD (1% yeast extract, 2% peptone, and 2% dextrose) at the given temperatures. +, growth; −+, moderate growth inhibition; −−+, severe growth inhibition; −, no growth at the indicated temperature.