The Mysterious Tip-Vesicles in Germinating Pollen Tube
Other conference paper


摘要Fertilization in flowering plants happens through pollination. The pollen grain, upon
germination on a receptive stigma, carrying the sperm cells to the embryo sac (Cheung et al.,
2010). Interestingly, the polarized pollen tube growth is characterized by abundant vesicles
important for both endocytosis and exocytosis (Grebnev et al., 2017). However, the nature,
identity and specific function of these highly dynamic vesicles remain elusive. To address these
questions, we will carry out ultrastructural and biochemical studies on growing pollen tube.
First, we will study the nature and types of tip-region vesicles using 3D electron tomography
(ET) analysis on pollen tube samples prepared by high pressure freezing-freeze substitution
according to our well-established procedures in root cells (Zhuang et al., 2017; Cui et al., 2019).
Second, we will investigate the possible roles of distinct vesicles in endocytosis and exocytosis.
The results based on the ET analysis on Vesicles-PM (plasma membrane) relationship will
explain the fusion events in the tip region. Third, we will develop protocols to purify vesicles
from the tip regions of germinating pollen tubes for subsequent protein analysis using Tandem
Mass Spectrometry. The purification and identification of purified vesicles will be further
confirmed by regular transmission electron microscopy (TEM) and cryo-EM examination.
Last, a novel monoclonal antibody library will be generated and screened from the protein
epitopes extracted from the purified vesicles for subsequent cellular biology study. Overall,
this study will provide new insights into the manipulation of fast-growing single-cell system
through the understanding of the biological function of tip-vesicles during pollen tube growth.
This work is supported by Research Grants Council of Hong Kong (CUHK14100818, C4011-
14R, C4012-16E, C4002-17G and AoE/M-05/12), CUHK and NSFC.
著者Zhiqi Liu, Kenneth Cheung, Liwen Jiang
會議名稱The 18th International Workshop on Plant Membrane Biology (IWPMB2019)

上次更新時間 2020-05-06 於 15:12