Botanisches Institut, Universität München, Menzinger Straße 67, D-8000, München 19, Federal Republic of Germany.
Planta. 1978 Jan;141(3):273-7. doi: 10.1007/BF00388343.
Phytochrome was determined in etiolated laminae of Avena sativaL. either without pretreatment or after 5 min of red irradiation followed by different periods of darkness (0-24 h). At given intervals laminae were homogenized and phytochrome was determined spectrophotometrically in the total homogenate and in purified etioplasts and mitochondria. Enhanced specific activity of phytochrome was found in all fractions after the irradiation in comparison to dark controls. Phytochrome destruction was observed in all fractions at the beginning of the subsequent dark period. Whereas the homogenate and the mitochondrial fraction showed a continuous destruction so that phytochrome reached a level far below that in etiolated plants, the phytochrome level in the plastid fraction reacheda minimum at 2 h with a subsequent increase beyond the dark level. This increase was most pronounced between 4 and 8 h after the red irradiation. The results are discussed in terms of the destruction and possible de novo synthesis of phytochrome that may be different in mitochondria and plastids.
在未预处理或红光照射 5 分钟后，用不同时间的黑暗（0-24 小时）处理后，测定了 Avena sativaL 的黄化叶片中的光敏色素。在给定的时间间隔内，将叶片匀浆，并在总匀浆以及纯化的黄化质体和线粒体中分光光度法测定光敏色素。与黑暗对照相比，照射后所有分数中的光敏色素比活性增强。在随后的黑暗期开始时，所有分数中都观察到光敏色素的破坏。虽然匀浆和线粒体分数表现出连续的破坏，以至于光敏色素达到远低于黄化植物水平的水平，但质体分数中的光敏色素水平在 2 小时达到最低，随后超过黑暗水平增加。这种增加在红光照射后 4 至 8 小时之间最为明显。根据可能在线粒体和质体中不同的光敏色素的破坏和可能的从头合成，讨论了这些结果。
