Richter P, Schuster M, Wagner H, Lebert M, Häder DP (2002)
Publication Status: Published
Publication Type: Journal article
Publication year: 2002
Publisher: Elsevier
Book Volume: 159
Pages Range: 181-190
Journal Issue: 2
The unicellular freshwater flagellate Euglena gracilis and its close relative Astasia longa show a pronounced negative gravitaxis. Previous experiments revealed that gravitaxis is most likely mediated by an active physiological mechanism in which changes of the internal calcium concentration and the membrane potential play an important role. In a recent parabolic flight experiment on board an aircraft (ESA 29th parabolic flight campaign), changes of graviorientation, membrane potential and the cytosolic calcium concentration upon changes of the acceleration (between 1 x g(n), 1.8 x g(n), microgravity) were monitored by image analysis and photometric methods using Oxonol VI (membrane potential) and Calcium Crimson (cytosolic calcium concentration). The parabolic flight maneuvers performed by the aircraft resulted in transient phases of 1.8 x g(n) (about 20s), microgravity (about 22s) followed by 1.8 x g(n) (about 20s). A transient increase in the intracellular calcium concentration was detected from lower to higher accelerations (1 x g(n) to 1.8 x g(n) or microgravity to 1.8 x g(n)). Oxonol VI-labeled cells showed a signal, which indicates a depolarization during the transition from 1 x g(n) to 1.8 x g(n), a weak repolarization in microgravity followed by a rapid repolarization in the subsequent 1 x g(n) phase. The results show good coincidence with observations of recent terrestrial and space experiments.
APA:
Richter, P., Schuster, M., Wagner, H., Lebert, M., & Häder, D.-P. (2002). Physiological parameters of gravitaxis in the flagellate Euglena gracilis obtained during a parabolic flight campaign. Journal of Plant Physiology, 159(2), 181-190. https://doi.org/10.1078/0176-1617-00605
MLA:
Richter, Peter, et al. "Physiological parameters of gravitaxis in the flagellate Euglena gracilis obtained during a parabolic flight campaign." Journal of Plant Physiology 159.2 (2002): 181-190.
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