Rxivist logo

COP9 signalosome is an essential and druggable parasite target that regulates protein degradation

By Swagata Ghosh, Laura Farr, Aditya Singh, Laura-Ann Leaton, Jay Padalia, David Sullivan, Shannon Moonah

Posted 25 Mar 2020
bioRxiv DOI: 10.1101/2020.03.24.004531

Understanding how the protozoan protein degradation pathway is regulated could uncover new parasite biology for drug discovery. We found the COP9 signalosome (CSN) conserved in multiple pathogens such as Leishmania, Trypanosoma, Toxoplasma, and used the severe diarrhea-causing Entamoeba histolytica to study its function in medically significant protozoa. We show that CSN is an essential upstream regulator of parasite protein degradation. Genetic disruption of E. histolytica CSN by two distinct approaches inhibited cell proliferation and viability. Both CSN5 knockdown and dominant negative mutation trapped cullin in a neddylated state, disrupting UPS activity and protein degradation. In addition, zinc ditiocarb (ZnDTC), a main metabolite of the inexpensive FDA-approved alcohol-abuse drug disulfiram, was active against parasites acting in a COP9-dependent manner. ZnDTC, given as disulfiram-zinc, had oral efficacy in clearing parasites in vivo. Our findings provide insights into the regulation of parasite protein degradation, and supports the significant therapeutic potential of COP9 inhibition.

Download data

  • Downloaded 144 times
  • Download rankings, all-time:
    • Site-wide: 86,735 out of 100,737
    • In microbiology: 7,198 out of 8,937
  • Year to date:
    • Site-wide: 41,465 out of 100,737
  • Since beginning of last month:
    • Site-wide: 55,546 out of 100,737

Altmetric data

Downloads over time

Distribution of downloads per paper, site-wide


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


  • 20 Oct 2020: Support for sorting preprints using Twitter activity has been removed, at least temporarily, until a new source of social media activity data becomes available.
  • 18 Dec 2019: We're pleased to announce PanLingua, a new tool that enables you to search for machine-translated bioRxiv preprints using more than 100 different languages.
  • 21 May 2019: PLOS Biology has published a community page about Rxivist.org and its design.
  • 10 May 2019: The paper analyzing the Rxivist dataset has been published at eLife.
  • 1 Mar 2019: We now have summary statistics about bioRxiv downloads and submissions.
  • 8 Feb 2019: Data from Altmetric is now available on the Rxivist details page for every preprint. Look for the "donut" under the download metrics.
  • 30 Jan 2019: preLights has featured the Rxivist preprint and written about our findings.
  • 22 Jan 2019: Nature just published an article about Rxivist and our data.
  • 13 Jan 2019: The Rxivist preprint is live!