应用激光共聚焦显微镜和全内反射荧光显微镜,以青杄花粉为供试材料,研究γ-氨基丁酸(gammaamino butyric acid,GABA)合成抑制剂3-MP对线粒体活动规律以及活性氧(reactive oxygen species,ROS)分布范围的影响。结果表明:正常条件下,线粒体的活动规律为由花粉管基部移动到亚顶端后随即发生回流,并主要集中在花粉管的顶端和亚顶端;3-MP处理后,线粒体前移并充满整个花粉管的膨胀区,同时花粉管中快速移动线粒体的比例也逐渐减少。此外,正常条件下,花粉管的顶端区域存在一个以顶端为基础的陡峭的ROS梯度;用3-MP处理后,ROS由花粉管顶端扩散至整个膨胀区。这些结果丰富了GABA影响裸子植物花粉极性生长的研究。
The effect of glutamate decarboxylase on pollen tube development in Picea wilsonii was investigated by using 3-mercaptopropionic acid( 3-MP) as an inhibitor,together with confocal microscopy studies and total internal reflection fluorescence microscopy( TIRFM) analysis. The results showed that the motility and distribution of mitochondria and ROS were affected by 3-MP.Under normal conditions,mitochondria moved beneath the plasma membrane toward the sub apex where they turned and moved away from center of the tube toward the base,therefore mitochondria were mainly concentrated in apex and sub apex of the pollen tube. In contrast,with 3-MP treatment,the mitochondria extended to the whole expansion area,and the proportion of rapid moving mitochondria decreased. Moreover,under normal conditions,ROS gradient was detected at the top of the pollen tube,but it was located in the whole expansion area of the pollen tube when treated with 3-MP. These results provided useful information about the effects of GABA on mitochondria and ROS dynamics in gymnosperms pollen tube growth.