This project is concerned with analyses of the genetic diversity of medically important parasitic protozoa and its implications to the epidemiology, course, and diagnosis of disease. The project has become increasingly involved in isolation of diversity at the DNA level. We have developed a method to synchronize the DNA synthetic cycle of trypanosomatids using very high levels of hydroxyurea. We are utilizing the technique for the production of large quantities of synchronized cells for elucidation and analyses of cell cycle-specific and developmental stage-specific substances. We have recently identified the presence in kinetoplastids of cytoplasmic DNA elements which contain kDNA minicircles and mitochondrial proteins. We are utilizing topoisomerase inhibitors to further analyze these DNA particles. It is possible that these particles represent the sites of guide RNA synthesis in the kinetoplastids. We have developed the technology to analyze the DNA synthetic cycle of amoeba by flow cytometry. The technique overcomes the problem of nonspecific background fluorescence which exists when amoeba are prepared for flow cytometry by conventional methods. The low-light- level video microscopy techniques developed for the study of the interaction of malaria merozoites with erythrocytes has been expanded to include the interaction of Trypanosoma cruzi and Toxoplasma gondii with vertebrate cells.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Intramural Research (Z01)
Project #
1Z01AI000099-23
Application #
3768725
Study Section
Project Start
Project End
Budget Start
Budget End
Support Year
23
Fiscal Year
1993
Total Cost
Indirect Cost
City
State
Country
United States
Zip Code
Tokumasu, Fuyuki; Ostera, Graciela R; Amaratunga, Chanaki et al. (2012) Modifications in erythrocyte membrane zeta potential by Plasmodium falciparum infection. Exp Parasitol 131:245-51
Tokumasu, Fuyuki; Nardone, Glenn A; Ostera, Graciela R et al. (2009) Altered membrane structure and surface potential in homozygous hemoglobin C erythrocytes. PLoS One 4:e5828
Ostera, Graciela; Tokumasu, Fuyuki; Oliveira, Fabiano et al. (2008) Plasmodium falciparum: food vacuole localization of nitric oxide-derived species in intraerythrocytic stages of the malaria parasite. Exp Parasitol 120:29-38
Calvo, Eric; Tokumasu, Fuyuki; Marinotti, Osvaldo et al. (2007) Aegyptin, a novel mosquito salivary gland protein, specifically binds to collagen and prevents its interaction with platelet glycoprotein VI, integrin alpha2beta1, and von Willebrand factor. J Biol Chem 282:26928-38
Hayakawa, Eri; Tokumasu, Fuyuki; Nardone, Glenn A et al. (2007) A Mycobacterium tuberculosis-derived lipid inhibits membrane fusion by modulating lipid membrane domains. Biophys J 93:4018-30
Arie, Takayuki; Fairhurst, Rick M; Brittain, Nathaniel J et al. (2005) Hemoglobin C modulates the surface topography of Plasmodium falciparum-infected erythrocytes. J Struct Biol 150:163-9
Tokumasu, Fuyuki; Fairhurst, Rick M; Ostera, Graciela R et al. (2005) Band 3 modifications in Plasmodium falciparum-infected AA and CC erythrocytes assayed by autocorrelation analysis using quantum dots. J Cell Sci 118:1091-8
Tokumasu, Fuyuki; Hwang, Jeeseong; Dvorak, James A (2004) Heterogeneous molecular distribution in supported multicomponent lipid bilayers. Langmuir 20:614-8
Tokumasu, Fuyuki; Jin, Albert J; Feigenson, Gerald W et al. (2003) Atomic force microscopy of nanometric liposome adsorption and nanoscopic membrane domain formation. Ultramicroscopy 97:217-27
Tokumasu, F; Dvorak, J (2003) Development and application of quantum dots for immunocytochemistry of human erythrocytes. J Microsc 211:256-61

Showing the most recent 10 out of 21 publications