Scientists from Heidelberg University Hospital have identified a mechanism through which malaria parasite move from the salivary gland of a mosquito through a person's skin into the body.
Malaria is caused by plasmodia, tiny parasites that enter the human body through the saliva of a mosquito when it bites.
They use active movements to enter into the bloodstream and from there to cells of the liver and finally into blood cells.
By using microscopic technique, the research team discovered that the parasite continually alternates between phases of rapid gliding and phases of firm adhesion to the surface.
The interaction of these two processes probably enables the parasite to move rapidly over a long time, which is necessary for successful transmission of the disease.
The researchers observed how the sporozoites adhere to several sites on the surface via the TRAP protein and then use the short actin filaments to push their body past these adhesion points.
"The parasite can stretch forward while still attaching with its rear end - thus building up elastic energy. At the moment when the rear adhesion is detached, energy is released and the sporozoite glides forward rapidly," said Dr. Friedrich Frischknecht.
The researchers call this mechanism the "stick-slip" method.
The speed of movement is regulated by the formation and turnover of adhesion sites, the existence and dynamics of which have been described for the first time.
The research is published in the prestigious journal "Cell Host and Microbe".