Richter P, Lebert M, Tahedl H, Häder DP (2001)
Publication Type: Journal article
Publication year: 2001
Publisher: Elsevier
Book Volume: 27
Pages Range: 983 - 988
DOI: 10.1016/S0273-1177(01)00163-6
Euglena gracilis is a photosynthetic, unicellular flagellate found in eutrophic freshwater habitats. The organisms control their vertical position in the water column using gravi- and phototaxis. Recent experiments demonstrated that negative gravitaxis cannot be explained by passive buoyancy but by an active physiological mechanism. During space experiments, the threshold of gravitaxis was determined to be between 0.08 and 0.12 × g. A strong correlation between the applied acceleration and the intracellular cAMP and Ca2+ was observed. The results support the hypothesis, that the cell body of Euglena, which is denser than the surrounding medium exerts a pressure onto the lower membrane and activates mechano-sensitive Ca2+ channels. Changes in the membrane potential and the cAMP concentration are most likely subsequent elements in a signal transduction chain, which results in reorientation strokes of the flagellum. © 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.
APA:
Richter, P., Lebert, M., Tahedl, H., & Häder, D.-P. (2001). Physiological characterization of gravitaxis in Euglena gracilis and Astasia longa studied on sounding rocket flights. Advances in Space Research, 27, 983 - 988. https://dx.doi.org/10.1016/S0273-1177(01)00163-6
MLA:
Richter, Peter, et al. "Physiological characterization of gravitaxis in Euglena gracilis and Astasia longa studied on sounding rocket flights." Advances in Space Research 27 (2001): 983 - 988.
BibTeX: Download