Expression of TRP1, but not exogenous tryptophan, rescues the delay in colony formation in sea3Δ mutants. (A) Fivefold serial dilutions of wild-type and sea3Δ mutants in the break-induced replication (BIR) assay strain with and without the addition of the TRP1 plasmid pRS414 on YPD and YPGal. The wild-type-in and sea3∆::LEU2-in strains have been previously experienced HO-induction with galactose and undergone a repair event, rendering them unable to undergo HO-mediated DSB induction upon replating on galactose. (B) Fivefold serial dilutions of the wild-type and sea3Δ BIR assay strain mutants plated on YPD, YPGal, YPD + 100 μM tryptophan (Trp) and YPGal + 100 μM Trp. (C) Western blots showing Tat2-3XFlag levels post-galactose induction at the indicated time points. Whole-cell extracts were prepared and blotted with α-Flag. Images are representative of three independent experiments. (D) Fivefold serial dilutions of the wild-type and sea3Δ mutants in the BIR assay strain were plated on YPD, YPGal and YPD and YPGal with either 2 or 4 μM quinolinic acid (QA) added. Plates were imaged on day 3, day 4, and day 5.