Figure 2.

hTERT expression permits telomere maintenance and allows T-Ag-transformed HEK cells to overcome crisis. (A) Genomic DNA was isolated from the parental line and the control and hTERT-infected populations and hybridized with a telomeric probe to visualize the TRF. The relative migration of molecular weight markers are on the left. (B) Culture growth (pd) versus time (days) are shown for polyclonal populations of T-Ag-transformed HEK cells infected with the control retrovirus (○) or the hTERT-expressing retrovirus (•). (C) Culture growth (pd) versus time (days) are shown for clonal isolates infected with the control retrovirus (open symbols: ○, □, ⋄, ▵, ▿) or the hTERT-expressing retrovirus (closed symbols: •, ■, ♦, ▴, ▾).