GENERATIVE CELL SPECIFIC 1 is essential for angiosperm fertilization
GENERATIVE CELL SPECIFIC 1 is essential for angiosperm fertilization
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DOI：
10.1038/ncb1345
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发表时间：
2006-01-01
影响因子：
21.3
通讯作者：
Kuroiwa, T
中科院分区：
文献类型：
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作者：
Mori, T;Kuroiwa, H;Kuroiwa, T
被子植物中的双受精过程是基于由花粉管（雄配子体）输送一对精细胞，花粉管向胚囊（雌配子体）延伸，胚囊中包含一个卵和一个中央细胞。一些研究已经描述了配子体相互作用的机制（1），以及受精过程-从授粉到花粉管接受（2-5）。然而，配子相互作用的机制尚未完全了解（6，7）。细胞学研究表明，雄配子具有不同的细胞表面结构（8，9），并且在cDNA文库中检测到雄配子特异性基因（10-14）。因此，对孤立配子的研究可能为理解精卵相互作用提供线索.在这项研究中，我们确定了一个新的蛋白质，命名为GCS 1（生殖细胞特异性1），从百合花粉生殖细胞分离。GCS 1具有一个羧基末端跨膜结构域，其同源物存在于包括非被子植物在内的多种物种中。免疫学分析表明，GCS 1是积累在晚期配子发生，并定位于生殖细胞的质膜上。此外，拟南芥GCS 1突变体配子不能融合，导致雄性不育，这表明GCS 1是被子植物中一个关键的受精因子。
The double fertilization process in angiosperms is based on the delivery of a pair of sperm cells by the pollen tube ( the male gametophyte), which elongates towards an embryo sac ( the female gametophyte) enclosing an egg and a central cell. Several studies have described the mechanisms of gametophyte interaction(1), and also the fertilization process - from pollination to pollen tube acceptance(2-5). However, the mechanisms of gamete interaction are not fully understood(6,7). Cytological studies have shown that male gametes possess distinct cell- surface structures(8,9) and genes specific to male gametes have been detected in cDNA libraries(10-14). Thus, studies of isolated gametes may offer clues to understanding the sperm - egg interaction. In this study, we identified a novel protein, designated GCS1 ( GENERATIVE CELL SPECIFIC 1), using generative cells isolated from Lilium longiflorum pollen. GCS1 possesses a carboxy- terminal transmembrane domain, and homologues are present in various species, including non-angiosperms. Immunological assays indicate that GCS1 is accumulated during late gametogenesis and is localized on the plasma membrane of generative cells. In addition, Arabidopsis thaliana GCS1 mutant gametes fail to fuse, resulting in male sterility and suggesting that GCS1 is a critical fertilization factor in angiosperms.