Does the shape of Plasmodium falciparum gametocytes have a function?
The gametocytes of Plasmodium falciparum have a characteristic banana-shape. One could wonder if this shape has been retained by selection forces because it favored transmission. By increasing the surface to volume ratio, the elongation that takes place during the maturation of P. falciparum gametocytes increases the susceptibility of gametocytes to rheological forces. This may facilitate their exit from the bone marrow and their subsequent impaction in the cutaneous capillaries that are lined with sequestered asexual parasites. The asymmetric curvature of gametocytes may tend to present gametocytes perpendicularly to the axis of the blood flow, thus increasing their chance to be retained and accumulate where they can be absorbed by the vector.
Nacher
Mathieu
M
Shoklo Malaria Research Unit, Mae Sod, Thailand. m_nacher@lycos.com
D000818:Animals; D005075:Biological Evolution; D055592:Biophysical Phenomena; D001703:Biophysics; D001783:Blood Flow Velocity; D048429:Cell Size; D005718:Gametogenesis / Q000502:physiology*; D005854:Germ Cells / Q000166:cytology* / Q000502:physiology*; D008018:Life Cycle Stages; D016778:Malaria, Falciparum / Q000635:transmission; D010963:Plasmodium falciparum / Q000166:cytology* / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D012100:Reproduction, Asexual; D012212:Rheology; D012641:Selection, Genetic