Study Of Cytoskeleton During The Germination Process Of Pollen Of Cunniughamia Lanceolata Hook

The research of plant developmental biology was one of the most active research area of Cunninghamia lauceolata. Pollen germination and pollen tube growth were the important link to complete sexual reproduction of seed plants while the microfilaments and microtubules were important to pollen germination and pollen tube growth.The distribution of microfilaments in the pollen and pollen tube of Cunninghamia lanceolata Hook were observed by fluorescence labeling and confocal laser scanning microscope. When pollen was germinating, microfilaments were distributed in the cytoplasm, the thick F-actin bundles form around the nuclear surface;After pollen germinated, microfilaments bundles distributed axially in the pollen tube of Cunninghamia lanceolata Hook;Microfilaments were formed a dense layer in the tip of pollen tube. We also found circular F-actin in germinated pollen and pollen tube. Compare to the study of some angiosperms, the density of microfilaments in the pollen and pollen tubes were different between the Cunninghamia lanceolata Hook and some angiosperms. The results sugguested that the density differences could be related to the slow rate of pollen tube growth in Cunninghamia lanceolata Hook.Using indirect immunofluorescence labeling, we found that microtubules were arranged obliquely or transversely in germinated pollen of Cunninghamia lanceolata Hook. After pollen germinated, Microtubules in pollen grain and the basal of pollen tube formed a obliquely or transversely array. In the middle of pollen tube, microtubules are arranged along the longitudinal axis. In some germinated pollen tubes, microtubules were arranged obliquely or transversely and extended to the pollen tube apex. Most microtubules were localized in the cortical of the pollen and pollen tube. In the pollen tube apex , there were different distribution as following:1.Microtubules formed an array beneath the plasma membrane that was perpendicular to the direction of tube growth. 2. Microtubules were arranged obliquely or transversely in the pollen tube apex. 3. Microtubules formed a complex network in the tip of pollen tube.