Phototropin Influence on Eyespot Development and Regulation of Phototactic Behavior in Chlamydomonas reinhardtii
Trippens J, Greiner A, Schellwat J, Neukam M, Rottmann T, Lu Y, Kateriya S, Hegemann P, Kreimer G (2012)
Publication Status: Published
Publication Type: Journal article
Publication year: 2012
Journal
Publisher: American Society of Plant Biologists
Book Volume: 24
Pages Range: 4687-4702
Journal Issue: 11
Abstract
The eyespot of Chlamydomonas reinhardtii is a light-sensitive organelle important for phototactic orientation of the alga. Here, we found that eyespot size is strain specific and downregulated in light. In a strain in which the blue light photoreceptor phototropin was deleted by homologous recombination, the light regulation of the eyespot size was affected. We restored this dysfunction in different phototropin complementation experiments. Complementation with the phototropin kinase fragment reduced the eyespot size, independent of light. Interestingly, overexpression of the N-terminal light, oxygen or voltage sensing domains (LOV1+LOV2) alone also affected eyespot size and phototaxis, suggesting that aside from activation of the kinase domain, they fulfill an independent signaling function in the cell. Moreover, phototropin is involved in adjusting the level of channelrhodopsin-1, the dominant primary receptor for phototaxis within the eyespot. Both the level of channelrhodopsin-1 at the onset of illumination and its steady state level during the light period are downregulated by phototropin, whereas the level of channelrhodopsin-2 is not significantly altered. Furthermore, a light intensity-dependent formation of a C-terminal truncated phototropin form was observed. We propose that phototropin is a light regulator of phototaxis that desensitizes the eyespot when blue light intensities increase.
Authors with CRIS profile
Jessica Trippens
Professur für Zellbiologie
Theresa Reimann
Lehrstuhl für Molekulare Pflanzenphysiologie
Georg Kreimer
Professur für Zellbiologie
Involved external institutions
Germany (DE)
India (IN)How to cite
APA:
Trippens, J., Greiner, A., Schellwat, J., Neukam, M., Rottmann, T., Lu, Y.,... Kreimer, G. (2012). Phototropin Influence on Eyespot Development and Regulation of Phototactic Behavior in Chlamydomonas reinhardtii. The Plant Cell, 24(11), 4687-4702. https://dx.doi.org/10.1105/tpc.112.103523
MLA:
Trippens, Jessica, et al. "Phototropin Influence on Eyespot Development and Regulation of Phototactic Behavior in Chlamydomonas reinhardtii." The Plant Cell 24.11 (2012): 4687-4702.
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