­­­­A Novel Pipeline to Elucidate the Adaptation Response to the G2/M DNA Damage Checkpoint

In response to genotoxic stresses, the DNA damage checkpoint is essential for maintaining genomic integrity and guaranteeing survival to the offspring. Checkpoints halt cell cycle progression to provide cells with the opportunity of repairing the damage. Once the damage is repaired, cell cycle progression resumes in a process known as recovery. On the contrary, if the lesions persist, cells are either cleared by apoptosis, quenched by senescence or enter mitosis with faulty DNA. This checkpoint-overriding process is known as adaptation. Although most of the cells that undergo adaptation die, a few manage to survive. Among the surviving cells, some will die in the following cell cycle, but a small percentage will eventually divide despite the damage in its genome. Evidence exists that adaptation contributes to genomic instability and may drive the selection of therapyresistant cells in oncology patients. Despite the dangerous nature and the clinical relevance of the process, adaptation is largely overlooked and has not been investigated in depth likely because of the difficulty to experimentally tackle the question. Here, we propose a pipeline for a systematic investigation of the process in Saccharomyces cerevisiae , that foresees population studies to track checkpoint markers, coupled with live-imaging to follow cell cycle parameters with the ultimate goal of contributing to making the study of adaptation reproducible and reliable.Funding Information: This work was supported in part by the Italian Ministry of Health with Ricerca Corrente and 5x1000 funds and by an International Early Career Scientist grant from the Howard Hughes Medical Institute to R.V.. A.D. is a PhD student at the European School of Molecular Medicine (SEMM). A.D. was supported by the FIRC-AIRC fellowship "Luca Erizzo". Declaration of Interests: The authors declare no competing interests.