Microtubule Organization in Pollen and Pollen Tube of Cunninghamia lanceolata
Microfilaments in the pollen and pollen tube of Cunninghamia lanceolata was observed by indirect immunofluorescence labeling and a confocal laser scanning microscope. We found that microtubules were arranged obliquely or transversely in the germinated pollen. After pollens germinated, microtubules in pollen grain and the basal of pollen tube formed an oblique or transverse array. In the middle of pollen tube, microtubules were 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 microtubule distributions 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.