【作者】 刘俊梅；

【导师】 张红； 李岩； 高志奎；

【作者基本信息】 河北农业大学 ， 蔬菜学， 2001， 硕士

【摘要】 微丝、微管作为细胞骨架的主要成份，广泛存在于真核生物中，并参与细胞内众多的生命活动。花粉萌发、花粉管伸长是种子植物实现有性生殖的重要环节，而微丝、微管系统在其中具有重要作用，因而研究其内细胞骨架具有重要意义。然而，目前尚缺乏关于较原始的裸子植物花粉管内细胞骨架的研究。本试验以素有“活化石”之称的银杏萌发花粉为材料，进行其内微丝、微管系统的研究。 通过荧光定位，对微丝的研究表明：银杏花粉及花粉管内都存在浓密的微丝网络，在水合、活化及花粉管伸长的各个不同的阶段，微丝分布呈明显的变化，花粉及花粉管内也存在循环分布的微丝；但与被子植物相比有明显的差异。银杏花粉内，微丝明显的聚集于膜上；花粉管顶端存在浓密的微丝网络，尤其在花粉萌发后期膨大的花粉管顶端都充满了浓密微丝网络；在偶尔出现的花粉管的分枝内，也有微丝分布；花粉管的周质部位存在许多由细小微丝组成的网络；在核周围充满辐射状排列的微丝，据此推测核可能是一个微丝的组织中心。同时，也观察到，在管核转向时，有明显的微丝转向。微丝与肌球蛋白的双标显示，两者存在共分布，同时与核的标记表明：微丝、肌球蛋白在管核周围也存在共分布，这表明微丝系统在管核的转向过程中可能具有重要作用。 通过间接免疫荧光定位，对微管的研究表明：银杏花粉及花粉管内存在浓密的微管网络，且其分布随花粉所处的状态不同而有所不同。其内微管多分布于周质，花粉管顶端有较多的微管。更多还原

【Abstract】 Microtubules (MTs) and microfllaments (MFs) exist extensively in all eukaryotic cells as major components of cytoskeleton. They are involved in many essential cellular functions in plant cells. Pollen germination and pollen tube growth in which the MFs and MTs are important are crutial to complete sexual reproduction for seed plants. Now it is still absent from the report about MFs and MTs in relatively primitive gymnosperm. We investigated the MFs and MTs in germinated pollen and pollen tube of Ginkgo biioba L. known as 憀iving fossil? By the chemical fixation and fluorescent labeling, the study on MFs showed that there exist dense MFs network in germinated pollen and pollen tube of GingAv biloba L. and different distribution in different stage. We can also see there are circular MFs in germinated pollen and pollen tube. Compared to the F-actin distribution in germinated pollen and pollen tube of angiosperm, that of Gin.~sko biloba L. is mainly distinguished as following, (a). We found obvious spot in membrane where MFs concentrated in germinated pollen of Gingko biloba L.. (b). MFs network is rich in the apical dome of pollen tube, especially in the swollen pollen tube late during the pollen tube growth. In addition, a lot of fine MFs arrays are present in the cortical of the whole pollen tube and there scatter MFs in scarcely branched tube. (c). Investigation indicated radial dense F-actin arrays around the nucleus in germinated pollen and pollen tube and we supposed that the nLIcleLIsmaybe serve as a MFs organizing center. (d). When the tube nucleus changed its movement direction during pollen germination, the F-actin in pollen changed their distribution direction. Double labeling between MFs and myosin manifested co- localization occurred and also appeared around the tube nucleus. Those implied that MFs system was important during the change in the direction of tube nucleus. Using indirect immunofluorescence labeling, we found that MTs filled in germinated pollen and pollen tube of Ginkgo biloba L.. Most MTs were localized in the cortical of the pollen and pollen tube. In the pollen tube apex there was also thick MTs array network.更多还原