Dataset Information

A genome-wide screen for essentiality upon telomerase inhibition identifies a novel p53 regulator, C16ORF72/TAPR1 [RNA-seq]

ABSTRACT: Telomere erosion in cells with insufficient levels of the telomerase reverse transcriptase, TERT, contributes to age-associated tissue dysfunction and senescence, and p53 plays a crucial role in this response. We undertook a genome-wide screen to identify gene deletions that sensitized p53-positive human cells to telomerase inhibition. We uncovered a previously unannotated gene, C16ORF72, which we term Telomere Attrition and p53 Response 1, TAPR1, that exhibited a synthetic-sick relationship with TERT loss. A genome-wide screen in TAPR1-disrupted cells also identified TERT as a sensitizing gene deletion. Additional genetic and transcriptome analysis of TAPR1-disrupted cells revealed that TAPR1 tapered p53 activation in response to eroded telomeres, p53 stabilization with nutlin-3a, or DNA damage. Importantly, deletion of TP53 rescued the fitness defect in TAPR1-disrupted cells. These findings identify C16ORF72/TAPR1 as new regulator at the nexus between telomere integrity and p53 regulation.

ORGANISM(S): Homo sapiens

PROVIDER: GSE160865 | GEO | 2021/03/04

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Aging is the consequence of intra- and extracellular events that promote cellular senescence. Dyskeratosis congenita (DC) is an example of a premature aging disorder caused by underlying telomere/telomerase-related mutations. Cells from these patients offer an opportunity to study telomere-related aging and senescence. Our previous work has found that telomere shortening stimulates DNA damage responses (DDR) and increases reactive oxygen species (ROS), thereby promoting entry into senescence. This work also found that telomere elongation via TERT expression, the catalytic component of the telomere-elongating enzyme telomerase, or p53 shRNA could decrease ROS by disrupting this telomere-DDR-ROS pathway. To further characterize this pathway, we performed a CRISPR/Cas9 knockout screen to identify genes that extend lifespan in DC cells. Of the cellular clones isolated due to increased lifespan, 34% had a guide RNA (gRNA) targeting CEBPB while gRNAs targeting WSB1, MED28 and p73 were observed multiple times. CEBPB is a transcription factor associated with activation of proinflammatory response genes suggesting that inflammation may be present in DC cells. The inflammatory response was investigated using RNA-Seq to compare DC and control cells. Expression of inflammatory genes were found to be significantly elevated (p<0.0001) in addition to a key subset of these inflammation-related genes (IL1B, IL6, IL8, IL12A, CXCL1 (GROa), CXCL2 (GROb), and CXCL5) which are regulated by CEBPB. Exogenous TERT expression led to downregulation of RNA/protein CEBPB expression and the inflammatory response genes suggesting a telomere-length dependent mechanism to regulate CEBPB. Furthermore, unlike exogenous TERT and p53 shRNA, CEBPB shRNA did not significantly decrease ROS suggesting that CEBPB’s contribution in DC cells’ senescence is ROS-independent. Our findings demonstrate a key role for CEBPB in engaging senescence by mobilizing an inflammatory response within DC cells.

Dataset Information

A genome-wide screen for essentiality upon telomerase inhibition identifies a novel p53 regulator, C16ORF72/TAPR1 [RNA-seq]

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure