Figure 3.

Telomere Elongation during In Vivo Reprogramming Depends on Telomerase Activity

(A and B) Left: representative immuno-FISH images showing OCT4 (green) and telomeres (red) in (A) the stomach and (B) the pancreas of i4F G1Terc^−/− reprogrammable mice after induction of in vivo reprogramming. White dashed lines mark the reprogrammed areas. Scale bars, 25 μm. Right: quantification of telomere signal in in vivo reprogrammed cells and the corresponding non-reprogrammed control cells. Telomere lengthening during in vivo reprogramming is abolished in the absence of telomerase activity. Error bars denote SE. n, number of nuclei. Number of mice analyzed = 3.

(C) Comparison of telomere lengthening during in vivo reprogramming in i4F and i4F G1Terc^−/− reprogrammable mice. Note that most of the telomere elongation observed during in vivo reprogramming is dependent on telomerase activity. Error bars denote SE. Statistical analysis by Student's t test. n, number of tissues from independent mice analyzed.

See also Figure S1.