【摘要】 应用荧光显微技术、激光共聚焦扫描显微技术、单克隆抗体免疫荧光标记技术以及傅里叶变换显微红外光谱分析(FTIR)等手段,研究了内钙拮抗剂TMB-8对白皮松花粉管胞内Ca2+分布、花粉管生长以及细胞壁构建等的影响。结果表明,白皮松花粉管经TMB-8处理后,胞内的Ca2+浓度下降,花粉管内典型的Ca2+浓度梯度消失,花粉萌发和花粉管生长均受到不同程度的抑制,抑制效果与拮抗剂浓度呈正相关。在对照中,纤维素和胼胝质在花粉管细胞壁上均匀分布,酸性果胶质仅分布在花粉管管壁上,而酯化果胶质仅分布于花粉管顶端;经TMB-8处理后,花粉管顶端纤维素、胼胝质以及酸性果胶质含量增加,而酯化果胶质含量减少。这些表明胞内Ca2+对花粉管顶端Ca2+浓度梯度的建成具有重要的作用,抑制胞内Ca2+释放可以影响花粉管细胞壁的结构组成和物理性质,从而抑制花粉管的生长。更多还原

【Abstract】 The effects of TMB-8,an intracellular calcium antagonist,on the pollen tube growth and cell wall construction in Pinus bungeana were investigated by means of fluorescence microscopy,laser scanning confocal microscopy,immunofluorescence technique and Fourier transform infra-red(FTIR) microspectroscopy.The results showed that TMB-8 inhibited P.bungeana pollen germination and tube growth in a dose-dependent manner.Normally growing pollen tubes displayed a typical tip-focused cytosolic free Ca2+ concentration gradient,while the Ca2+ concentration gradient dissipated in TMB-8-treated pollen tubes.Cellulose and callose were distributed uniformly in the wall of pollen tubes;acidic pectin was distributed in the tube wall except for the apex while esterified pectin was present only in the apex.In TMB-8-treated tubes,the content of cellulose,acidic pectin and callose increased while esterified pectin decreased in the apex compared with the normal tube wall.It indicated that the intracellular Ca2+ was necessary in the formation of apical cytosolic Ca2+ concentration gradient.Inhibition of intracellular Ca2+ release resulted in the arrest of pollen tube growth by the modification of cell wall composition in P.bungeana pollen tube.更多还原