Abstract:

Green fluorescent protein (GFP) fused to the F actin binding domain of mouse talin labels the actin cytoskeleton in the immature pollen of stable transformed rice ( Oryza sativa L.) plants. Actin microfilaments could be visualized only in the late developmental stage of the immature pollen. During this developmental stage, microfilaments, initially composed of very short fibrils, develop into a very complex and novel network that sometimes totally and sometimes partially encloses the vegetative nucleus and the spherical shaped generative cell in the central cytoplasm of the immature pollen. The behavior of the actin microfilamentous structure throughout the late developmental stage of the immature pollen is extremely dynamic, and the likelihood of this structure in generating forces for vegetative nucleus and generative cell movement in the immature pollen has been discussed. No actin filaments were visualized in the spherical generative cell

绿色荧光蛋白基因结合鼠Talin 基因蛋白标记转基因水稻未成熟花粉的微丝骨架
徐是雄^1* 王凌健^1,2   丘志平¹  叶永健¹ 余旭红^1,2

（1. 香港大学植物系，香港；2. 中国科学院上海植物生理生态研究所，上海200032）

摘要： 利用绿色荧光蛋白基因结合鼠Talin基因表达技术及水稻转基因技术，在未成熟花粉发育期（即生殖细胞在形成后从靠壁部位移向中央部位的阶段）的水稻（Oryza satixa L.）内发现了一系列前人未曾报道过的微丝骨架的形成和多变过程。在这一发育阶段，未成熟花粉内的生殖细胞呈圆形，中央部位存有一个大液泡，大量微丝在细胞的中央胞质内形成。微丝首先在营养核的核膜表面形成两个集结中心，中心内的微丝呈短粗状。尔后，中心微丝不断延长，最终在细胞中央的胞质内形成一个非常复杂的类似多个纺锤体结合在一起的网络结构。这一网络的中间部位经常包围着营养核和生殖细胞，网络的部分微丝则与存在周缘细胞质（或称周质）的微丝网络形成连接，在连接点部位则形成一些由微丝环状组成的结构。未成熟花粉中央的微丝网络可能与营养核和生殖细胞在未成熟花粉内的运动有密切关系。
关键词： 水稻；未成熟花粉；绿色荧光蛋白；鼠Talin; 微丝

Key words: Oryza sativa, pollen, green fluorescent protein (GFP), mouse talin, actin, microfilament