Ntefidou M, Richter P, Streb C, Lebert M, Häder DP (2002)
Publication Status: Published
Publication Type: Journal article
Publication year: 2002
Book Volume: 501
Pages Range: 301-302
In the absence of other external stimuli the motile, unicellular freshwater flagellate Euglena gracilis normally swims upward in the water column (negative gravitaxis). This behavior is most likely triggered by active physiological orientation mechanisms. Recently it was found that negative gravitaxis often inverts to a positive one upon high light exposure. This response is not mediated by the photoreceptor (the paraxonemal body - PAB), because PAB-free mutants do also show this response after high radiation. It is very likely that the phenomenon is triggered by reactive oxygen species, because in the absence of oxygen no gravitaxis sign change was observed. Also increased salinity inverses the sign of gravitaxis, leading to the assumption that environmental stressors induce the formation of reactive oxygen species, serving as signal molecules.
APA:
Ntefidou, M., Richter, P., Streb, C., Lebert, M., & Häder, D.-P. (2002). High light exposure leads to a sign change in gravitaxis of the flagellate Euglena gracilis. 18TH ESA SYMPOSIUM ON EUROPEAN ROCKET AND BALLOON PROGRAMMES AND RELATED RESEARCH, 501, 301-302.
MLA:
Ntefidou, Maria, et al. "High light exposure leads to a sign change in gravitaxis of the flagellate Euglena gracilis." 18TH ESA SYMPOSIUM ON EUROPEAN ROCKET AND BALLOON PROGRAMMES AND RELATED RESEARCH 501 (2002): 301-302.
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