To conduct the study, the researchers stained red blood cells infected with P. falciparum with two kinds of dye—one stained the blood cells green, the other stained the malaria parasites red.
In the first stage leading up to the merozoites' release, which the researchers dubbed the "irregular schizont" stage, the red blood cell resembles a lop-sided fried egg, with the parasites visible as a sphere near the center of the cell. The cell's lop-sided appearance may result from destruction of the cytoskeleton, the molecular scaffolding that helps the cell to maintain its rounded shape.
In the next stage, called the "flower" stage, the red blood cell assumes a roughly spherical shape, covered with rounded structures that resemble the petals of a flower.
In the final stage, the blood cell's membrane appears to break apart. At roughly the same time, cellular compartments, called vacuoles, which encase the newly formed merozoites, also break apart. The entire process has an explosive appearance, dispersing the merozoites some distance from the cell.
Image: Joshua Zimmerberg, September 20, 2005 Current Biology, "Membrane transformation during malaria parasite release from human red blood cells."
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