Objective: To investigate the role of transcription factors Sp1 and Sp3 in the regulation of telomerase activity and human telomerase reverse transcriptase (hTERT) in Jurkat T cells.
Methods: By way of lipofectamine, Sp1 and Sp3 expression vectors were transferred into Jurkat T cells in which the protein expression levels of Sp1 and Sp3 were examined by Western blotting. Telomerase PCR-ELISA was used to assess the telomerase activity, and telomerase-mediated DNA- ladders were analyzed by silver staining and hTERT mRNA level determined by reverse transcriptase-PCR (RT-PCR).
Results: Treatment of Jurkat T cells with Sp1 expression vector for 36 h resulted in significant increase in Sp1 and Sp3 protein levels by 59.6% (P<0.01) and 36.8% (P<0.05) respectively. Enhancement of Sp1 expression obviously increased telomerase activity and hTERT mRNA levels at a rate of 38.5% (P<0.05) and 25.4% (P<0.05) respectively, whereas Sp3 evinced no significant effect on both telomerase activity and hTERT mRNA levels.
Conclusion: Transcription factor Sp1, but not Sp3, regulates telomerase activity by altering hTERT mRNA levels in Jurkat T cells.