[SEMINAR – RSVP Only] The survival tactics of Plasmodium falciparum in erythrocytic stages

Date:      Wednesday, Dec 2, 2020 10:00 – 11:00

Location:              Seminar Room B503

Description:

Speaker:

Dr. Eri H Hayakawa

Div. of Medical Zoology, Department of Infection and Immunity, Jichi Medical University

Title:      The survival tactics of Plasmodium falciparum in erythrocytic stages

~ New evidences of intracellular structures of parasitized erythrocytes by modern electron microscopy techniques ~

Abstract:

Plasmodium falciparum (P. falciparum) parasites still cause lethal infections worldwide, especially in Africa. Due to no effective vaccine available for protection against malaria, basic study by new approaches and translational research are imperative. P. falciparum has unique aspects of protein transport system and lipid metabolism that is very different from other eukaryotic cells. For example, P. falciparum delivers over 400 proteins to the surface of erythrocytes that have no protein transport machinery. To transport newly synthesized parasite proteins to erythrocyte surface, Maurer’s clefts (MCs) appear in parasitized erythrocyte cytoplasm after invasion and are believed to play a crucial role for protein transportation, particularly maturations of the proteins. However, there were still unknown for fine 3D-structure, localization, and structural relationship between MCs and cytoskeletons. Furthermore, P. falciparum lacks a cholesterol synthesis passway, even cholesterol is essential for P. falciparum survival. For those principal issues, we found with “unroofing”-TEM observation; 1) the structure of MCs range from 200 nm to 700 nm and have easily-resolved tethers with 170 nm to 450 nm in length using, 2) parasitized-erythrocytes are often associated with budding membranes that elongate into the cytosol and the membrane segments migrate towards parasite, and finally, membrane cholesterol is taken up by parasites via Niemann Pick C1-like protein or its homologue proteins. Our results may help expanding possibility for new anti-malaria drug development.

** Only limited Seating available due to COVID-19 restrictions. **

Please RSVP by 12:00 Tuesday, Dec 1^st2020 to Shizuka.kuda@oist.jp