Hsp Regulation by PI3P is important for Plasmodium Falciparum

Throughout the world millions of people are affected by Plasmodium Falciparum, a parasite responsible for the transmission of the deadliest form of malaria.  Several molecules in the parasite work to keep it alive during transmission and infection; PI3P is one such lipid necessary for parasite growth but with an unknown signaling pathway. Previous work by the Derbyshire lab indicated that PfHsp70– a parasite heat shock protein– was a potential candidate for binding to PI3P in the parasite life cycle. Within PfHsp70 is a LID domain, usually responsible for binding to anionic lipids like PI3P. We believe that deletion of the LID domain in PfHsp70 will decrease its binding affinity to PI3P. To test this, both the Wild Type and LID-deleted PfHsp70 proteins were expressed (in yeast) and purified. Isothermal Titration Calorimetry will be used to quantitatively assess changes in binding affinity. In the ITC both the purified Wild Type and LID-deleted proteins will react with PI3P to produce a binding curve with heat released/absorbed plotted against concentration of PI3P. If a lower binding affinity is measured in the LID-deleted interaction, we will potentially know more about PI3P signaling and ways to disrupt PI3P synthesis to cause parasite death.