# Chemical Biology Strategies to Resolve Plasmodium Heat Shock Protein Function > **NIH NIH R01** · DUKE UNIVERSITY · 2024 · $522,780 ## Abstract Project Summary Despite modern efforts to eradicate malaria, the disease continues to threaten the lives of over half the world's population. The urgency to uncover novel drug targets in the blood and liver stages of Plasmodium parasites, the causative agents of malaria, is exacerbated by strains resistant to frontline antimalarials. To address this need, a better understanding of pathogen biology is imperative, particularly relating to essential, druggable proteins. The Plasmodium falciparum heat shock proteins 90 and 70-1 (PfHsp90 and PfHsp70-1) are molecular chaperones critical to multiple stages of the parasite's lifecycle. These proteins have N-terminal nucleotide binding domains (NBD) that hydrolyze ATP and C-terminal domains that are critical for protein binding and functional dimer formation. We previously identified several molecules that bind to the PfHsp90 NBD that potently inhibit Plasmodium, but the role of the C-terminus for protein function has not been fully explored. We also discovered that the PfHsp70-1 C-terminus has a critical role in lipid signaling under heat stress, but we lacked chemical probes to resolve the function of the NBD in this process. Thus, we need domain-specific small molecule probes to unravel the role of these protein domains in Plasmodium proteostasis and signaling. Our goal is to understand mechanisms that support Plasmodium protein homeostasis and signaling by investigating domain-specific PfHsp90 and PfHsp70-1 functions and to uncover their interactomes. In Aim 1, we plan to develop domain-specific chemical probes that target PfHsp90 and PfHsp70-1. Candidates discovered through target-based screening will be assessed for their affinity with biochemical methods and the ligand binding site will be established with the mass spectrometry approach stability of proteins from rates of oxidation (SPROX). Our preliminary efforts to date have yielded putative novel N-terminal and C-terminal binders for both chaperones that we will optimize and employ in biological studies. In Aim 2, we will investigate the PfHsp90 and PfHsp70-1 interactomes using our chemical probes and genetic tools, respectively, in thermal proteome profiling and limited proteolysis strategies. Prioritized chaperone interactors will be validated with biochemical methods. In Aim 3, we will leverage our PfHsp90 and PfHsp70-1 chemical probes to link chaperone domains to the transcriptional stress response, global protein regulation, and digestive vacuole stability in parasites. We will use RNA-sequencing to assess the transcriptome and develop bioorthogonal noncanonical amino acid tagging (BONCAn to label and track nascent proteins in Plasmodium after chemical probe addition. Digestive vacuole stabilization assays will be completed after chaperone inhibition using live-cell microscopy. Together, this work will identify and characterize parasitic molecular networks involving PfHsp90 and PfHsp70-1 to gain insight into their biological function. Our c... ## Key facts - **NIH application ID:** 10851824 - **Project number:** 5R01AI173295-02 - **Recipient organization:** DUKE UNIVERSITY - **Principal Investigator:** Emily R Derbyshire - **Activity code:** R01 (R01, R21, SBIR, etc.) - **Funding institute:** NIH - **Fiscal year:** 2024 - **Award amount:** $522,780 - **Award type:** 5 - **Project period:** 2023-06-01 → 2028-05-31 ## Primary source NIH RePORTER: https://reporter.nih.gov/project-details/10851824 ## Citation > US National Institutes of Health, RePORTER application 10851824, Chemical Biology Strategies to Resolve Plasmodium Heat Shock Protein Function (5R01AI173295-02). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10851824. Licensed CC0. --- *[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*