Institute of Plant Sciences, University of Granz, Austria.
Plant Signal Behav. 2011 Sep;6(9):1259-62. doi: 10.4161/psb.6.9.16722.
Glutathione is an important antioxidant and redox buffer in plants. Despite its crucial roles in plant metabolism and defense in the sporophyte, its roles in the gametophyte are largely unexplored. Recently, we demonstrated that glutathione synthesis is essential for pollen germination in vitro. In this study, we extend these results and focus on the subcellular distribution of glutathione in pollen grains and compare it to the situation in the sporophyte. Glutathione was equally distributed within mitochondria, plastids, nuclei and the cytosol in the gametophyte -- in contrast to youngest fully developed leaves and root tips of the sporophyte, where glutathione was highest in the mitochondria, followed by nuclei, cytosol, peroxisomes and plastids in decreasing concentration. Glutathione was not detected in vacuoles. We can conclude that glutathione synthesis is essential for pollen germination in vitro and that the subcellular distribution of glutathione in the gametophyte differs significantly from the sporophyte.
谷胱甘肽是植物中一种重要的抗氧化剂和氧化还原缓冲剂。尽管它在孢子体的代谢和防御中起着至关重要的作用，但它在配子体中的作用在很大程度上还未被探索。最近，我们证明了谷胱甘肽的合成对于花粉在体外的萌发是必不可少的。在这项研究中，我们扩展了这些结果，并专注于谷胱甘肽在花粉粒中的亚细胞分布，并将其与孢子体的情况进行比较。在配子体中，谷胱甘肽均匀分布在线粒体、质体、细胞核和细胞质中——与孢子体中最年轻的完全发育的叶片和根尖形成鲜明对比，在那里，谷胱甘肽在线粒体中含量最高，其次是细胞核、细胞质、过氧化物酶体和质体，浓度依次降低。在液泡中未检测到谷胱甘肽。我们可以得出结论，谷胱甘肽的合成对于花粉在体外的萌发是必不可少的，并且谷胱甘肽在配子体中的亚细胞分布与孢子体有很大的不同。
