Ssu72 is required for polymerase α activation Ssu72 is required for polymerase α activation ssu72+ and pol1+ regulate telomere length in the same genetic pathway. Epistasis analysis of ssu72∆ and pol1‐13 mutants was performed by Southern blotting of ApaI‐digested DNA using a telomeric probe.Stn1‐Pol1 interaction requires Ssu72 phosphatase. Immunoprecipitation experiments of Pol1‐Flag with Stn1‐Myc were performed in both wt and ssu72∆ mutants.Immunoprecipitation of Ten1‐Flag with Stn1‐Myc in either wt or ssu72∆ was performed as control for Stn1‐Ten1 complex integrity.Overexpression of polymerase alpha partially rescues telomere length defect of ssu72Δ mutants. Multicopy vector with polymerase α under thiamine promoter was expressed in both wt and ssu72Δ cells.Model for Ssu72 regulation of telomere replication in fission yeast. See text for details. Jose Miguel Escandell et al. EMBO J. 2019;38:e100476 © as stated in the article, figure or figure legend