Rxivist logo

CRISPR-Cas9 Screens In Human Cells And Primary Neurons Identify Modifiers Of C9orf72 Dipeptide Repeat Protein Toxicity

By Michael S. Haney, Nicholas J. Kramer, David W Morgens, Ana Jovičić, Julien Couthouis, Amy Li, James Ousey, Rosanna Ma, Gregor Bieri, Michael C. Bassik, Aaron D. Gitler

Posted 21 Apr 2017
bioRxiv DOI: 10.1101/129254 (published DOI: 10.1038/s41588-018-0070-7)

Hexanucleotide repeat expansions in the C9orf72 gene are the most common cause of amyotrophic lateral sclerosis and frontotemporal dementia (c9FTD/ALS). The nucleotide repeat expansions are translated into dipeptide repeat (DPR) proteins, which are aggregation-prone and may contribute to neurodegeneration. Studies in model organisms, including yeast and flies have converged upon nucleocytoplasmic transport as one underlying pathogenic mechanism, but a comprehensive understanding of the molecular and cellular underpinnings of DPR toxicity in human cells is still lacking. We used the bacteria-derived clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 system to perform genome-wide gene knockout screens for suppressors and enhancers of C9orf72 DPR toxicity in human cells. We validated hits by performing secondary CRISPR-Cas9 screens in primary mouse neurons. Our screens revealed genes involved in nucleocytoplasmic transport, reinforcing the previous findings from model systems. We also uncovered new potent modifiers of DPR toxicity whose gene products function in the endoplasmic reticulum (ER), proteasome, RNA processing pathways, and in chromatin modification. Since regulators of ER stress emerged prominently from the screens, we further investigated one such modifier, TMX2, which we identified as a modulator of the ER-stress signature elicited by C9orf72 DPRs in neurons. Together, this work identifies novel suppressors of DPR toxicity that represent potential therapeutic targets and demonstrates the promise of CRISPR-Cas9 screens to define mechanisms of neurodegenerative diseases.

Download data

  • Downloaded 3,892 times
  • Download rankings, all-time:
    • Site-wide: 1,269 out of 94,912
    • In genetics: 95 out of 4,824
  • Year to date:
    • Site-wide: 17,379 out of 94,912
  • Since beginning of last month:
    • Site-wide: 26,425 out of 94,912

Altmetric data

Downloads over time

Distribution of downloads per paper, site-wide


Sign up for the Rxivist weekly newsletter! (Click here for more details.)