Cryo-EM structure of the Plasmodium falciparum 80S ribosome bound to the anti-protozoan drug emetine
- Walter and Eliza Hall Institute of Medical Research, Australia
- Medical Research Council Laboratory of Molecular Biology, United Kingdom
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Australia
- Imperial College London, United Kingdom
Abstract
Malaria inflicts an enormous burden on global human health. The emergence of parasite resistance to front-line drugs has prompted a renewed focus on the repositioning of clinically approved drugs as potential anti-malarial therapies. Antibiotics that inhibit protein translation are promising candidates for repositioning. We have solved the cryo-EM structure of the cytoplasmic ribosome from the human malaria parasite, Plasmodium falciparum, in complex with emetine at 3.2 Å resolution. Emetine is an anti-protozoan drug used in the treatment of ameobiasis that also displays potent anti-malarial activity. Emetine interacts with the E-site of the ribosomal small subunit and shares a similar binding site with the antibiotic pactamycin, thereby delivering its therapeutic effect by blocking mRNA/tRNA translocation. As the first cryo-EM structure that visualizes an antibiotic bound to any ribosome at atomic resolution, this establishes cryo-EM as a powerful tool for screening and guiding the design of drugs that target parasite translation machinery.
Article and author information
Author details
Reviewing Editor
- Werner Kühlbrandt, Max Planck Institute of Biophysics, Germany
Publication history
- Received: April 14, 2014
- Accepted: June 6, 2014
- Accepted Manuscript published: June 9, 2014 (version 1)
- Version of Record published: July 8, 2014 (version 2)
Copyright
© 2014, Wong et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Cryo-EM structure of the Plasmodium falciparum 80S ribosome bound to the anti-protozoan drug emetine
eLife 3:e03080.
https://doi.org/10.7554/eLife.03080
Further reading
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- Structural Biology and Molecular Biophysics
Human adult muscle-type acetylcholine receptors are heteropentameric ion channels formed from two α-subunits, and one each of the β-, d-, and e-subunits. To form functional channels, the subunits must assemble with one another in a precise stoichiometry and arrangement. Despite being different, the four subunits share a common ancestor that is presumed to have formed homopentamers. The extent to which the properties of the modern-day receptor result from its subunit complexity is unknown. Here we discover that a reconstructed ancestral muscle-type β-subunit can form homopentameric ion channels. These homopentamers open spontaneously and display single-channel hallmarks of muscle-type acetylcholine receptor activity. Our findings attest to the homopentameric origin of the muscle-type acetylcholine receptor, and demonstrate that signature features of its function are both independent of agonist and do not necessitate the complex heteropentameric architecture of the modern-day protein.
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- Biochemistry and Chemical Biology
- Structural Biology and Molecular Biophysics
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