Acetaldehyde, a metabolite of ethanol, is a cellular toxicant and a human carcinogen. A genome-wide CRISPR-based loss-of-function screen in erythroleukemic K562 cells revealed candidate genetic contributors affecting acetaldehyde cytotoxicity. Secondary screening exposing cells to a lower acetaldehyde dose simultaneously validated multiple candidate genes whose loss results in increased sensitivity to acetaldehyde. Disruption of genes encoding components of various DNA repair pathways increased cellular sensitivity to acetaldehyde. Unexpectedly, the tumor suppressor gene OVCA2, whose function is unknown, was identified in our screen as a determinant of acetaldehyde tolerance. Disruption of the OVCA2 gene resulted in increased acetaldehyde sensitivity and higher accumulation of the acetaldehyde-derived DNA adduct N2-ethylidene-dG. Together these results are consistent with a role for OVCA2 in adduct removal and/or DNA repair.
Bibliographical noteFunding Information:
This work was supported by grant from the Superfund Hazardous Substance Research and Training Program (P42ES004705 to M.T.S.) as well as support from the University of Florida, Gainesville to C.V. A.S. was a trainee in the Superfund Research Program (University of California, Berkeley). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute of Environmental Health Sciences.
- CRISPR screening
- DNA repair