PHOTOINDUCTION OF FORMATION OF CIRCULAR STRUCTURES BY MICROFILAMENTS ON CHLOROPLASTS DURING INTRACELLULAR ORIENTATION IN PROTONEMAL CELLS OF THE FERN ADIANTUM-CAPILLUS-VENERIS
PHOTOINDUCTION OF FORMATION OF CIRCULAR STRUCTURES BY MICROFILAMENTS ON CHLOROPLASTS DURING INTRACELLULAR ORIENTATION IN PROTONEMAL CELLS OF THE FERN ADIANTUM-CAPILLUS-VENERIS
复制标题
DOI：
10.1007/bf01353585
复制
发表时间：
1992-01-01
期刊：
影响因子：
2.9
通讯作者：
WADA, M
中科院分区：
文献类型：
--
作者：
KADOTA, A;WADA, M
用罗丹明-鬼笔环肽染色法研究了铁线蕨（Adiantum capillus-veneris）原丝细胞在光敏色素介导和蓝光诱导的叶绿体光定向过程中皮层肌动蛋白微丝的组织变化。用20 μ m宽的微束对单个细胞进行部分照射，诱导低和高注量率反应。在低注量率的反应，以红色和蓝色光，一个圆形的结构组成的微丝诱导的叶绿体集中在照射区域，面向质膜的一侧，已经报道的情况下，低注量率的反应诱导的偏振红色或蓝色光。在离微束较远的叶绿体上没有观察到这种结构。时间过程的研究表明，该结构诱导后，叶绿体聚集在照明区域和该结构消失之前，叶绿体移出该区域时，微束被关闭。在高注量率蓝光响应中，叶绿体避开照射部位，但聚集在靠近微束边缘的阴影区域。在该区域聚集的叶绿体上也观察到由微丝组成的圆形结构，并且在光/暗制度期间，它的出现和消失与低通量率响应的情况下表现出相同的行为。然而，没有这样的圆形结构中观察到的高通量率响应红光，在这种情况下，叶绿体也避免了照明区域，但没有在邻近地区的积累诱导。这些结果表明，由微丝组成的环状结构可能在叶绿体的细胞内光定向过程中起着锚定作用。
Changes in the organization of cortical actin microfilaments during phytochrome-mediated and blue light-induced photoorientation of chloroplasts were investigated by rhodamine-phalloidin staining in protonemal cells of the fem Adiantum capillus-veneris. Low- and high-fluence rate responses were induced by partial irradiation of individual cells with a microbeam of 20-mu-m in width. In the low-fluence rate responses to red and blue light, a circular structure composed of microfilaments was induced on the chloroplast concentrated in the irradiated region, on the side facing the plasma membrane, as already reported in the case of the low-fluence rate response induced by polarized red or blue light. Such a structure was not observed on the chloroplasts located far from the microbeam. Time-course studies revealed that the structure was induced after the chloroplasts gathered in the illuminated region and that the structure disappeared before chloroplasts moved out of this region when the microbeam was turned off. In the high-fluence rate response to blue light, chloroplasts avoided the irradiated site but accumulated in the shaded area adjacent the edges of microbeam. The circular structure made of microfilaments was also observed on the chloroplasts gathered in the area and it showed the same behavior with respect to its appearance and disappearance during a light/dark regime as in the case of the low-fluence rate response. However, no such circular structure was observed in the high-fluence rate response to red light, in which case the chloroplasts also avoided the illuminated region but no accumulation in the adjacent areas was induced. These results indicate that the circular structure composed of microfilaments may play a role in the anchorage of the chloroplast during intracellular photo-orientation.