A team from Harvard and the Broad Institute documents artemisinin resistance mutations in West African isolates of the malaria-causing parasite Plasmodium falciparum. Using drug sensitivity assays, genome sequencing, gene editing, and other approaches, the researchers tracked the rise of resistance-related mutations in two culture-adapted P. falciparum isolates from Senegal that were intermittently exposed to artemisinin in the lab for up to four years. From suspicious mutations detected in seven genes, they took a closer look at alterations affecting a gene coding for a conserved, WD40-propellor domain family protein Pfcoronin.
For another paper in the Proceedings of the National Academy of Sciences, investigators at Chicago's Field Museum of Natural History take a look at interactions between more than 1,700 ant species and 10,785 vascular plant genera with the help of time-scaled plant phylogenetic information. By examining feeding, foraging, nesting, and other ant interactions with plants, the team traced ant-plant interactions back to the Mesozoic era, documenting a range of specializations in the plants and ants since then. "Together, the evidence suggests that ants and plants increasingly relied on one another and incrementally evolved more intricate associations with different macroevolutionary consequences as angiosperms increased their ecological dominance," the authors note.
Researchers in the US, Czech Republic, and Bangladesh describe histone methylation shifts that coincide with undernourishment in children from Bangladesh. The team used chromatin immunoprecipitation sequencing to profile histone modifications in blood samples collected over time from around 700 children from an urban slum in Bangladesh enrolled in an ongoing longitudinal study. In the undernourished infants, the investigators saw changes in the distribution of H3 lysine 4 trimethylation (H3K4me3) marks, particularly around genes contributing to metabolic and immune processes. GenomeWeb has more on the study, here.