DNA repair during sleep in single neuron (IMAGE) Bar-Ilan University Caption During waking hours (top) the buildup of DNA damage in neurons increases tiredness. Acting as an "antenna" the PARP1 protein (yellow helmets) senses and marks DNA breaks in cells, drives sleep, and recruits repair systems (green and blue helmets, bottom). During sleep, the DNA repair systems repair the breaks enabling a fresh new start to the day. In red is the soma (cell body), blue the nucleolus, and green (DNA damage sites). Credit Dr. David Zada Usage Restrictions None License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.