title: Coupling of Retrograde Flow to Force Production During Malaria Parasite Migration.
abstract: Migration of malaria parasites is powered by a myosin motor that moves actin filaments, which in turn link to adhesive proteins spanning the plasma membrane. The retrograde flow of these adhesins appears to be coupled to forward locomotion. However, the contact dynamics between the parasite and the substrate as well as the generation of forces are complex and their relation to retrograde flow is unclear. Using optical tweezers we found retrograde flow rates up to 15 μm/s contrasting with parasite average speeds of 1-2 μm/s. We found that a surface protein, TLP, functions in reducing retrograde flow for the buildup of adhesive force and that actin dynamics appear optimized for the generation of force but not for maximizing the speed of retrograde flow. These data uncover that TLP acts by modulating actin dynamics or actin filament organization and couples retrograde flow to force production in malaria parasites.
authors.affiliation: Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School , Im Neuenheimer Feld 324, 69120 Heidelberg, Germany.
authors.forename: Katharina A
authors.initials: KA
authors.lastname: Quadt
authors.affiliation: Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School , Im Neuenheimer Feld 324, 69120 Heidelberg, Germany.|University of Heidelberg , Department of Biophysical Chemistry and Max Planck Institute for Intelligent Systems, Department of New Materials and Biosystems, Heisenbergstr. 3, 70569 Stuttgart, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Streichfuss
authors.affiliation: Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School , Im Neuenheimer Feld 324, 69120 Heidelberg, Germany.
authors.forename: Catherine A
authors.initials: CA
authors.lastname: Moreau
authors.affiliation: University of Heidelberg , Department of Biophysical Chemistry and Max Planck Institute for Intelligent Systems, Department of New Materials and Biosystems, Heisenbergstr. 3, 70569 Stuttgart, Germany.
authors.forename: Joachim P
authors.initials: JP
authors.lastname: Spatz
authors.affiliation: Integrative Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School , Im Neuenheimer Feld 324, 69120 Heidelberg, Germany.
authors.forename: Friedrich
authors.initials: F
authors.lastname: Frischknecht
mesh_terms: D000199:Actins / Q000737:chemistry / Q000378:metabolism; D000818:Animals; D001696:Biomechanical Phenomena; D002465:Cell Movement / Q000502:physiology*; D008288:Malaria / Q000469:parasitology*; D051379:Mice; D010962:Plasmodium berghei / Q000737:chemistry / Q000502:physiology*; D015800:Protozoan Proteins / Q000737:chemistry* / Q000378:metabolism*; D034101:Sporozoites / Q000737:chemistry / Q000502:physiology*
chemical_list: D000199:Actins; D015800:Protozoan Proteins
keywords: Plasmodium; cell migration; gliding motility; laser traps; malaria; sporozoites