The functional importance of telomere clustering: Global changes in gene expression result from SIR factor dispersion

Silencing efficiency reflects both the local concentration of SIR proteins and the strength of SIR factor recruitment. (A) Silencing of the URA3 reporter gene at a truncated Tel7L is monitored by the percentage of cells growing on 5-FOA in WT (GA-1053) or full deletion derivatives yku70 (GA-1055), esc1 (GA-2411), yku70 esc1 (GA-148), rif1 (GA-3214), rif1 yku70 (GA-3213), esc1 rif1, and yk70 rif1 esc1 (GA-3215). Colonies are shown on the right panel for WT (GA-1053), or its yku70 (GA-1055), rif1 yku70 (GA-3213), and yk70 rif1 esc1 (GA-3215) derivatives. (B) Immunolocalization of Sir4 and nuclear pores (MAb414) in WT, yku70, yku70 rif1, or yk70 rif1 esc1 strains.