Phenotypic Screens Identify Parasite Genetic Factors Associated with Malarial Fever Response inPlasmodium falciparum piggyBacMutants.
Malaria remains one of the most devastating parasitic diseases worldwide, with 90% of the malaria deaths in Africa in 2013 attributable toPlasmodium falciparum. The clinical symptoms of malaria include cycles of fever, corresponding to parasite rupture from red blood cells every 48 h. Parasite pathways involved in the parasite's ability to survive the host fever response, and indeed, the functions of ~40% ofP. falciparumgenes as a whole, are still largely unknown. Here, we evaluated the potential of scalable forward-genetic screening methods to identify genes involved in the host fever response. We performed a phenotypic screen for genes linked to the parasite response to febrile temperatures by utilizing a selection of single-disruptionP. falciparummutants generated via randompiggyBactransposon mutagenesis in a previous study. We identified several mutants presenting significant phenotypes in febrile response screens compared to the wild type, indicating possible roles for the disrupted genes in this process. We present these initial studies as proof that forward genetics can be used to gain insight into critical factors associated with parasite biology.IMPORTANCEThough theP. falciparumgenome sequence has been available for many years, ~40% of its genes do not have informative annotations, as they show no detectable homology to those of studied organisms. More still have not been evaluated via genetic methods. Scalable forward-genetic approaches that allow interrogation of gene function without any pre-existing knowledge are needed to hasten understanding of parasite biology, which will expedite the identification of drug targets and the development of future interventions in the face of spreading resistance to existing frontline drugs. In this work, we describe a new approach to pursue forward-genetic phenotypic screens forP. falciparumto identify factors associated with virulence. Future large-scale phenotypic screens developed to probe other such interesting phenomena, when considered in parallel, will prove a powerful tool for functional annotation of theP. falciparumgenome, where so much remains undiscovered.
Center for Global Health and Infectious Diseases Research, Department of Global Health, University of South Florida, Tampa, Florida, USA.
Phaedra
P
Thomas
Center for Global Health and Infectious Diseases Research, Department of Global Health, University of South Florida, Tampa, Florida, USA.
Jennifer
J
Sedillo
Center for Global Health and Infectious Diseases Research, Department of Global Health, University of South Florida, Tampa, Florida, USA.
Jenna
J
Oberstaller
Center for Global Health and Infectious Diseases Research, Department of Global Health, University of South Florida, Tampa, Florida, USA.
Suzanne
S
Li
Center for Global Health and Infectious Diseases Research, Department of Global Health, University of South Florida, Tampa, Florida, USA.
Min
M
Zhang
Center for Global Health and Infectious Diseases Research, Department of Global Health, University of South Florida, Tampa, Florida, USA.
Naresh
N
Singh
Center for Global Health and Infectious Diseases Research, Department of Global Health, University of South Florida, Tampa, Florida, USA.
Chengqi C Q
CC
Wang
Center for Global Health and Infectious Diseases Research, Department of Global Health, University of South Florida, Tampa, Florida, USA.
Kenneth
K
Udenze
Center for Global Health and Infectious Diseases Research, Department of Global Health, University of South Florida, Tampa, Florida, USA.
Rays H Y
RH
Jiang
Center for Global Health and Infectious Diseases Research, Department of Global Health, University of South Florida, Tampa, Florida, USA.
John H
0000-0003-3707-7979
JH
Adams
forward genetics; heat shock; phenotype screen; piggyBac; transposon-mediated mutagenesis; virulence factors