Figure 1. Increased rates of TERRA transcription lead to telomere processing in an Exo1-dependent manner and trigger recombination in HDR-proficient cells. (A–C) Growth curves, following a 24 h dilution protocol.³³ Average relative cell density is shown on the y-axis (set arbitrarily to 100) and average PDs on the x-axis. Mean and s.e.m. of six biological replicates are depicted for the indicated mutants. (D) 1L and 7L telomere PCR products of est2 7L-Gal tiTEL cells from (C). (E) Sequencing of 1L and 7L telomere PCR products from est2 7L-Gal tiTEL cells in (B) at PD 26. Open bars represent undiverged telomeres; red bars indicate divergence (indicative of HR). The point of divergence corresponds to where the red bar joins the open bar. (F) Comparison of the telomeric recombination frequency is shown as percent of telomeres with a recombination event (total number of telomeres analyzed for 1L: n = 39 and for 7L: n = 64).