Erythrocyte Membrane Protein 3 (EMAP3) Is Exposed on the Surface of the Plasmodium berghei Infected Red Blood Cell

Area of Science:

• Malariology
• Parasitology
• Cell Biology

Background:

• Malaria parasites like Plasmodium falciparum export proteins to infected red blood cells (iRBCs) for survival.
• These proteins mediate cytoadherence, preventing iRBCs from clearance by the spleen.
• Plasmodium berghei is a key model organism for studying malaria, with iRBCs sequestering via CD36-binding.

Purpose of the Study:

• To identify and characterize novel proteins exported to the iRBC surface in Plasmodium berghei.
• To investigate the role of the newly identified EMAP3 protein in iRBC cytoadherence and sequestration.
• To establish a platform for screening malaria cytoadherence inhibitors in vivo.

Main Methods:

• Identification and localization of the novel exported protein EMAP3 in P. berghei iRBCs.
• Genetic manipulation of P. berghei to generate EMAP3-deficient parasites.
• Assessment of parasite growth and CD36-mediated sequestration in EMAP3 knockout models.

Main Results:

• EMAP3 was identified and localized to the iRBC membrane, with EMAP3 exposed on the outer surface.
• Parasites lacking EMAP3 showed no significant reduction in growth or CD36-mediated sequestration.
• EMAP3 is not a major CD36-binding protein in P. berghei.

Conclusions:

• EMAP3 is an exported iRBC surface protein in P. berghei, potentially interacting with EMAP1.
• EMAP3's lack of significant role in sequestration suggests it's not a primary CD36 ligand.
• EMAP3 provides a novel scaffold for displaying P. falciparum proteins, enabling in vivo screening for cytoadherence inhibitors.