GSE24-2 reactivates telomerase in X-linked dyskeratosis congenita and VA13 cells. (A) Telomerase activity in X-linked dyskeratosis congenita patient lymphoblast cells obtained from a carrier mother (DC-C) and her affected children (DC-1, DC-2, and DC-3). Cells were transiently transfected with 3 μg of the empty vector (−) or GSE24-2 (+) per million cells. Telomerase activity was measured 24 hours later. (B) DC2 cells were transiently transfected with 3 μg pLNCX-, GSE24-2–, or DKC-expressing vectors, per million cells. Telomerase activity was measured 24 hours later. (C) Expression levels of hTERT and hTR in cells from one of the patients (DC-3) transfected with 3 μg of the empty vector or GSE2-2 per million cells. RNA levels were detected by RT-PCR. GAPDH was used as a control. (D) GMO1787 X-DC patient-derived fibroblasts were infected with pLNCX- or GSE24-2–derived viruses and stable cell lines were used to determine telomerase activity (total protein amount indicated in triangles). (E) Expression levels of hTERT and hTR in GMO1787 transfected with the pLNCX of pGSE24-2 plasmids were determined by RT-PCR. GAPDH was used as a control. (F) Growth rates of the GMO1787-transfected cells described in panel D are compared by cumulative PDLs with time. All the experiments were repeated 3 times, with similar results. (G) Telomerase activity in VA13 cells. Cells were transiently transfected with 16 μg pLNCX control vector or GSE24-2 per million cells. Telomerase activity was measured 24 hours later, using serial dilutions of protein extracts (total protein amount indicated in triangles). (H) Expression levels of hTERT and hTR in VA13 cells transfected with 16 μg pLNCX, DKC, or GSE24-2 plasmid per per million cells. RNA levels were determined by RT-PCR. GAPDH was used as a control.