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Imaging G-protein Coupled Receptor (GPCR)-mediated Signaling Events that Control Chemotaxis of Dictyostelium Discoideum
Published on: September 20, 2011
Graviperception in ciliates: steps in the transduction chain
R Hemmersbach1, M Krause, R Bräucker
1Institute of Aerospace Medicine, DLR, Cologne, Germany. ruth.hemmersbach@dlr.de
Advances in Space Research : the Official Journal of the Committee on Space Research (COSPAR)
|June 7, 2005
Summary
Ciliates exhibit gravity-induced behaviors, with cytoplasm acting as a statolith. Electrophysiological studies and parabolic flights reveal gravity response thresholds and relaxation in microgravity.
Area of Science:
- Cell Biology
- Biophysics
- Gravitational Biology
Background:
- Ciliates are excellent models for studying gravity perception and signal transduction.
- Their cytoplasm may function as a statolith, activating mechanosensitive ion channels.
Purpose of the Study:
- To investigate the role of cytoplasm as a statolith in ciliates.
- To analyze ciliate behavior under varying gravitational conditions.
Main Methods:
- Electrophysiological studies on Stylonychia mytilus.
- Behavioral analysis of Paramecium and Stylonychia during parabolic flights.
Main Results:
- Spatial orientation influences membrane potential (depolarization/hyperpolarization).
- Gravity responses relax in microgravity.
- Gravikinesis and gravitaxis thresholds identified at 0.4xg and 0.6xg, respectively.
Conclusions:
- Cytoplasm acts as a statolith, influencing cell membrane potential.
- Ciliates exhibit distinct gravity response thresholds and behaviors under microgravity.
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