Figure 4.

Analysis of the effects of ectopically tethering Rap1 to telomeres. (A) Diagram of GFP-Taz1^C-term and Rap1-GFP-Taz1^C-term. The expressions of both chimeric constructs are driven by the nmt1 promoter. Unless otherwise indicated, all GFP-Taz1^C-term experiments were performed in a taz1Δrap1⁺ background, and all Rap1-GFP-Taz1^C-term experiments were performed in a taz1Δrap1Δ background. (B) Effects of GFP-Taz1^C-term and Rap1-GFP-Taz1^C-term on telomere length regulation. Experiments were performed as in Figure 1A. (C) Telomeric 3′ overhang regulation in GFP-Taz1^C-term and Rap1-GFP-Taz1^C-term cells. Experiments were performed as in Figure 1B. (D) Analysis of telomere fusions in GFP-Taz1^C-term and Rap1-GFP-Taz1^C-term cells. Experiments were performed as in Figure 2. The strain represented in lanes 1 and 2 (taz1Δrap1Δ Rap1-GFP-Taz1^C-term) displays less ‘I' fragment, and correspondingly less ‘M+I' and ‘L+I' than the other strains, presumably because of mutations in the region containing the terminal Not1 site on the right arm of Chr I. (E) Growth of GFP-Taz1^C-term and Rap1-GFP-Taz1^C-term at 20°C. Experiments were performed as in Figure 3A.