Malaria remains a major global infectious disease, largely affecting people living in resource poor environments. Infection of humans with Plasmodium falciparum parasites results in significant morbidity and mortality. Drug- resistance is constantly undermining the usefulness of antimalarial regimens. It is imperative to identify new antimalarial drug targets to ensure the success of control and eradication efforts. Further, the call for malaria eradication requires an understanding of the determinants of parasite transmission. Plasmodium falciparum parasites utilize epigenetic machinery for the regulation of key processes within the parasitic life-cycle, including antigenic variation for persistence and pathogenesis during asexual proliferation, as well as for switching to sexual development for transmission through the parasitic life-cycle. We have obtained genetic evidence that the Class II histone deacetylases (HDACs) are essential for P. falciparum growth during the asexual cycle. We hypothesize that these P. falciparum HDACs regulate discrete and critical functions in the asexual and sexual biology of the parasite. Inhibition of these mechanisms will result in the specific killing of P. falciparum asexual and/or sexual forms. In this proposal, we will identify the essential functions of these enzymes that are responsible for asexual proliferation, conversion to the sexual stage, and sexual development for transmission. We will use a reverse genetics approach for the phenotypic analysis of mutant parasites in the asexual and sexual stages. We will probe the mechanistic basic of HDAC functions using a combination of bulk and single cell transcriptomics and epigenomics. Finally, we will uncover the precise mechanisms of action of the HDACs by dissecting the functions of their specific enzymatic domains, using biochemical and chemical genetic approaches. Together, these studies will serve to elucidate the functions of these critical epigenetic regulators in parasite biology relevant to asexual proliferation for virulence and sexual development for transmission, validating and characterizing these molecules as new targets for therapeutic development within the parasite.

Public Health Relevance

Malaria remains one of the greatest scourges of humankind, and it is critical that we continue to devise strategies that can both treat disease as well as lead to the elimination of transmission. In this work, we will target the Plasmodium falciparum histone deacetylase molecules that are essential for growth of the parasite in the blood, the stage of infection responsible for both virulence and transmission of the parasite. We will define the mechanisms by which these epigenetic regulator proteins function to provide a rational biological basis for antimalarial therapies.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI138551-02
Application #
9653110
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Mcgugan, Glen C
Project Start
2018-02-20
Project End
2023-01-31
Budget Start
2019-02-01
Budget End
2020-01-31
Support Year
2
Fiscal Year
2019
Total Cost
Indirect Cost
Name
Harvard University
Department
Microbiology/Immun/Virology
Type
Schools of Public Health
DUNS #
149617367
City
Boston
State
MA
Country
United States
Zip Code
02115