Nabieh Ayoub
Technion †Israel Institute of Technology, Israel
Title: NELFâ€E is recruited to DNA doubleâ€strand break sites to promote transcriptional repression and repair
Biography
Biography: Nabieh Ayoub
Abstract
Double-strand breaks (DSBs) trigger rapid and transient transcription pause to prevent collisions between repair and transcription machineries at damage sites. Little is known about the mechanisms that ensure transcription block after DNA damage. Here we reveal a novel role of the negative elongation factor, NELF, in blocking transcription activity nearby DSBs. We show that NELF-E and NELF-A are rapidly recruited to DSB sites. Furthermore, NELF-E recruitment and its repressive activity are both required for switching off transcription at DSBs. Remarkably, using I-Sce-I endonuclease and CRISPR-Cas9 systems, we observed that NELF-E is preferentially recruited, in a PARP1-dependent manner, to DSBs induced upstream transcriptionally active rather than inactive genes. Moreover, the presence of RNA polymerase II is a prerequisite for the preferential recruitment of NELF-E to DNA breakage sites. Additionally, we demonstrate that NELF-E is required for intact repair of DSBs. Altogether, our data identified NELF complex as a new component in the DNA damage response.