Toda Y, Murakami S
Department of Biology, University of Tokyo, Japan.
J Electron Microsc (Tokyo). 1995 Dec;44(6):450-5.
Changes in distribution of photosystem I (PS I) in the developing thylakoid membranes of greening barley (Hordeum vulgare L. cv. Amagi-Nijo) chloroplasts were studied by a cytochemical method using 3,3'-diaminobenzidine (DAB). The activity was detected on the thylakoid of etiochloroplasts after 1 h of greening. Stacks of a few thylakoids (thought to be an initiation of grana) appeared at about 2-3 h of greening. Until 4 h, the DAB reaction was observed uniformly throughout the whole thylakoid system (stroma and grana thylakoids). After 6 h of greening, The DAB reaction was detected heterogeneously in the etiochloroplasts; more intense on the stroma thylakoid and peripheral grana thylakoid. Further illumination led to more distinct heterogeneity of the DAB reaction. Thus, redistribution of PS I proceeded differentially after onset of grana formation in the developing etiochloroplasts. Measurements of chlorophyll content, light saturation of PS I activity and fluorescence emission spectra of greening barley leaves suggest that redistribution of PS I may reflect developmental changes in assembly of the PS I complex with light-harvesting chlorophyll-protein complex.
利用3,3'-二氨基联苯胺（DAB）的细胞化学方法，研究了绿化大麦（Hordeum vulgare L. cv. Amagi-Nijo）叶绿体发育中的类囊体膜中光系统I（PS I）分布的变化。绿化1小时后，在黄化叶绿体的类囊体上检测到活性。在绿化约2-3小时时，出现了几层类囊体堆叠（被认为是基粒的起始）。直到4小时，在整个类囊体系统（基质类囊体和基粒类囊体）中均观察到DAB反应。绿化6小时后，在黄化叶绿体中检测到DAB反应不均匀；在基质类囊体和周边基粒类囊体上更强烈。进一步光照导致DAB反应的异质性更加明显。因此，在发育中的黄化叶绿体中，基粒形成开始后，PS I的重新分布以不同方式进行。对绿化大麦叶片叶绿素含量、PS I活性的光饱和以及荧光发射光谱的测量表明，PS I的重新分布可能反映了PS I复合物与捕光叶绿素-蛋白质复合物组装过程中的发育变化。
