Department of Biological Sciences, University of Missouri, 65211, Columbia, MO, USA.
Photosynth Res. 1990 Apr;24(1):81-8. doi: 10.1007/BF00032647.
Photosynthesis mutations were induced in maize lines bearing the transposable DNA element system, Mutator. Two Photosystem I mutants (hcf101 and hcf104) which were isolated are described here. Maize plants homozygous for the hcf104 mutation are seedling lethal and exhibit a high in vivo chlorophyll fluorescence yield. They lack ∼60% of CP1, P700 and PSI-specific electron transport activity relative to normal sibling plants. The comparable depletion of these three measures of PS I content conforms to the pattern reported for many other PS I-deficient mutants. Maize plants homozygous for hcf101 are seedling lethal and also exhibit high in vivo chlorophyll fluorescence yield. They lack 80-90% of CP1 and P700 but sustain steady state levels of PS I-specific electron transport activity at 70% of normal. Previous reports of similar apparent PS I hyperactivity are discussed and an explanation for the elevated steady state level of PS I electron transport activity in hcf101 is proposed.
在携带可转座 DNA 元件系统 Mutator 的玉米品系中诱导光合作用突变。本文描述了两个分离的 Photosystem I 突变体(hcf101 和 hcf104)。hcf104 突变纯合的玉米植株是致死性的,并表现出高的体内叶绿素荧光产量。与正常的同胞植物相比,它们缺乏约 60%的 CP1、P700 和 PSI 特异性电子传递活性。这三种 PS I 含量的类似耗竭符合许多其他 PS I 缺陷突变体的报告模式。hcf101 纯合的玉米植株是致死性的,也表现出高的体内叶绿素荧光产量。它们缺乏 80-90%的 CP1 和 P700,但 PS I 特异性电子传递活性的稳态水平维持在正常的 70%。讨论了以前关于类似明显 PS I 超活性的报告,并提出了 hcf101 中 PS I 电子传递活性的稳态水平升高的解释。