High-throughput sequencing of an inducible CRISPR/Cas9 screen for positive regulators of hTERT transcription

Telomerase activity appears undetectable in most human somatic cells but present in ~90% of cancer and immortalized cells, underscoring the importance of upregulated telomerase activity to cancer development. Whereas telomerase RNA is highly and ubiquitously expressed even in tissues with no detectable telomerase activity, hTERT expression is exceedingly restricted in nearly all somatic cells. Transcriptional regulation is one of the most important factors for hTERT expression. To systematically search for hTERT transcriptional regulators, we performed an inducible CRISPR/Cas9 screen with a hTERT-EGFP reporter to identify positive regulators of hTERT transcription.