Concepedia

K13-propeller mutations confer artemisinin resistance in Plasmodium falciparum clinical isolates

Judith Straimer, Nina F. Gnädig, Benoît Witkowski, Chanaki Amaratunga, Valentine Duru, Arba Pramundita Ramadani, Mélanie Dacheux, Nimol Khim, Lei Zhang, Stephen C.-T. Lam,

Science · 2014 · 743 citations · 28 references

DOI

TL;DR

Artemisinin resistance emerging in Southeast Asia threatens global malaria control efforts. The authors used zinc‑finger nucleases to edit the K13 locus in Plasmodium falciparum and measured ring‑stage survival after drug exposure, linking these rates to patient parasite clearance times. Deleting K13 mutations lowered survival from 13–49% to 0.3–2.4%, while inserting them raised survival from ≤0.6% to 2–29%, demonstrating that K13 propeller mutations drive resistance and supporting worldwide K13 sequencing to detect and eliminate resistant parasites.

Abstract

The emergence of artemisinin resistance in Southeast Asia imperils efforts to reduce the global malaria burden. We genetically modified the Plasmodium falciparum K13 locus using zinc-finger nucleases and measured ring-stage survival rates after drug exposure in vitro; these rates correlate with parasite clearance half-lives in artemisinin-treated patients. With isolates from Cambodia, where resistance first emerged, survival rates decreased from 13 to 49% to 0.3 to 2.4% after the removal of K13 mutations. Conversely, survival rates in wild-type parasites increased from ≤0.6% to 2 to 29% after the insertion of K13 mutations. These mutations conferred elevated resistance to recent Cambodian isolates compared with that of reference lines, suggesting a contemporary contribution of additional genetic factors. Our data provide a conclusive rationale for worldwide K13-propeller sequencing to identify and eliminate artemisinin-resistant parasites.