A Plasmodium α/ß-hydrolase modulates the development of invasive stages.

The bud emergence (BEM)46 proteins are evolutionarily conserved members of the α/ß-hydrolase superfamily, which includes enzymes with diverse functions and a wide range of substrates. Here, we identified a Plasmodium BEM46-like protein (PBLP) and characterized it throughout the life cycle of the rodent malaria parasite Plasmodium yoelii. The Plasmodium BEM46-like protein is shown to be closely associated with the parasite plasma membrane of asexual erythrocytic stage schizonts and exo-erythrocytic schizonts; however, PBLP localizes to unique intracellular structures in sporozoites. Generation and analysis of P. yoelii knockout (Δpblp) parasite lines showed that PBLP has an important role in erythrocytic stage merozoite development with Δpblp parasites forming fewer merozoites during schizogony, which results in decreased parasitemia when compared with wild-type (WT) parasites. Δpblp parasites showed no defects in gametogenesis or transmission to mosquitoes; however, because they formed fewer oocysts there was a reduction in the number of developed sporozoites in infected mosquitoes when compared with WT. Although Δpblp sporozoites showed no apparent defect in mosquito salivary gland infection, they showed decreased infectivity in hepatocytes in vitro. Similarly, mice infected with Δpblp sporozoites exhibited a delay in the onset of blood-stage patency, which is likely caused by reduced sporozoite infectivity and a discernible delay in exo-erythrocytic merozoite formation. These data are consistent with the model that PBLP has an important role in parasite invasive-stage morphogenesis throughout the parasite life cycle.

CRISPR-Cas Technology In and Out of the Classroom.

Student-centered practices, including student-focused research opportunities, enhance biology education and comprehension. One way to support student interest is through research opportunities in faculty laboratories. However, alternatives to traditional research apprenticeships are important for the inclusion of more undergraduate students in CRISPR-Cas-based research. Student interest in CRISPR-Cas technologies serves as a timely focal point for deepening undergraduate student engagement in biology courses. In this article, we describe some of the ongoing efforts to bring CRISPR-Cas technology out of the classroom and into the teaching laboratory.