Gain setting inChlamydomonas reinhardtii: Mechanism of phototaxis and the role of the photophobic response
| العنوان: | Gain setting inChlamydomonas reinhardtii: Mechanism of phototaxis and the role of the photophobic response |
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| المؤلفون: | David N. Zacks, John L. Spudich |
| المصدر: | Cell Motility and the Cytoskeleton. 29:225-230 |
| بيانات النشر: | Wiley, 1994. |
| سنة النشر: | 1994 |
| مصطلحات موضوعية: | Organelles, Light, Rotation, Large dynamic range, Chlamydomonas reinhardtii, Cell Biology, Biology, biology.organism_classification, Light intensity, Cell Movement, Structural Biology, Botany, Retinaldehyde, Phototaxis, Biophysics, Animals, Eyespot, Light beam, Photoreceptor Cells, Invertebrate, Temporal change, Gain setting |
| الوصف: | The unicellular green alga (Chlamydomonas reinhardtii maintains sensitivity of its phototaxis response (alignment of swimming direction along the axis of a light beam) over several orders of magnitude of light intensities. It is widely accepted that the rotation of the swimming cell provides temporal comparisons of light intensities via periodic contrast generated by its asymmetrically positioned refractile eyespot organelle. The cells also exhibit a second behavioral response to light called the photophobic (or stop) response, which is a brief cessation of swimming caused by a temporal change in light intensity. The cells are desensitized to photophobic stimuli by light exposure. Through comparative measurements of both responses, we explain the behavioral basis of the large dynamic range of phototaxis in terms of precise desensitization of the photophobic response. The basis of the explanation is that the flagellar beat changes which cause phototactic orientation are the residual of the photophobic response after desensitization (i.e., "mini-photophobic" reactions which cause brief reorienting motions without a full stop). This interpretation predicts quantitatively the dependence of the extent of desensitization on light intensity and the dependence of onset and maintenance of phototaxis on extent of desensitization. These predictions are tested and confirmed in this report. |
| تدمد: | 1097-0169 0886-1544 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f8493b0c3af361e96fed7636f4d9e51dTest https://doi.org/10.1002/cm.970290305Test |
| حقوق: | CLOSED |
| رقم الانضمام: | edsair.doi.dedup.....f8493b0c3af361e96fed7636f4d9e51d |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 10970169 08861544 |
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