Supplementary Figure 6: Ectopic fl-TRF1 and fl-ΔA localize at telomeres.
From: TRF1 participates in chromosome end protection by averting TRF2-dependent telomeric R loops
(a) Flag immunostaining (green) combined with telomeric DNA FISH (red) on HeLa cells infected with pLPC-derived retroviruses expressing fl-TRF1 and fl-ΔA from a constitutive promoter. Numbers are percentages of cells expressing the ectopic proteins. (b) Flag (green) and TRF2 (red) immunostaining on U2OS cells infected with pLVX-TetOne-Puro-derived lentiviruses expressing fl-TRF1 or fl-ΔA from a doxycycline-inducible promoter. Cells were treated with doxycycline for 24 hours (+dox) or left untreated (-dox). Numbers are percentages of cells expressing the ectopic proteins. (c) Immunostaining using an anti-Flag antibody (green) combined with an antibody raised against a peptide comprising the acidic domain of TRF1 (red) on HeLa and U2OS cells infected with pLVX-TetOne-Puro-derived lentiviruses expressing fl-TRF1 or fl-ΔA. Cells were treated with doxycycline for 24 hours (+dox). Note that expression of fl-ΔA substantially reduces the signal generated by the TRF1 A domain antibody within the same cells indicating displacement of endogenous TRF1 from telomeres. Scale bars, 5 μm.
