| Autor: |
H. Oelze-Karow, H. Kasemir, Hans Mohr, G. Link |
| Rok vydání: |
1984 |
| Předmět: |
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| Zdroj: |
Advances in Photosynthesis Research ISBN: 9789024729456 |
| DOI: |
10.1007/978-94-017-4971-8_179 |
| Popis: |
In mustard seedling cotyledons phytochrome (Pfr) controls the biosynthesis of plastid matrix and thylakoid constituents, very probably at the transcriptional level of the nuclear and plastid genome. In this way Pfr stimulates the build-up of photosynthetically active chloroplasts and ensures the photostability of plastids during the first phase of greening. Once photostability is established, the further stability (at least of Chl) is no longer Pfr -dependent; rather it is a matter of Chl arrangement in plastid membranes. This has been shown by two series of experiments: (1) the seedlings were transferred from continuous white light to darkness with or without a long wavelength far-red light pulse treatment. (2) the seedlings were treated with intermittent light of red and red plus far-red light pulses. It has been shown that the stability of Chl a and the lability of Chl b over a period of 24 h in darkness is not dependent on Pfr. The Pfr-independence of plastid stability after light — dark tranarer lasts until the cotyledons begin to senesce. Once dark-mediated senescence comes into play plastid stability responds again to Pfr which prevents the disintegration of plastid membranes and the breakdown of the plastid genetic apparatus. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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