Gravitaxis Analysis of Paramecium (Results of a Space Experiment on a Sounding Rocket).

Abstract

A cell culture of Paramecium with a pronounced negative gravitaxis was exposed for 6 minutes to a 10-6g during a parabolic flight of a sounding rocket. Swimming orientation, swimming velocity and indivi- vidual swimming tracks were registered in real time by means of a fully automatic image analysis system. Additionally, cells were fixed after landing for analysis of the amount of trichocysts. The result obtained confirm and complete our ground-based experiments under hyper-gravity in a low-speed centrifuge microscope (NIZEMI) and underthe conditions of simulated weightlessness in a fast-rotating clino- stat. Due to the fact that Paramecium shows clear and fast responses if the influence of gravity is changed it seems to be an ideal test system for investigating the mechanisms of graviperception in single cells.