Localization of arabinogalactan-proteins in different stages of embryos and their role in cotyledon formation of Nicotiana tabacum L.
Localization of arabinogalactan-proteins in different stages of embryos and their role in cotyledon formation of Nicotiana tabacum L.
复制标题
阿拉伯半乳聚糖蛋白在胚胎不同阶段的定位及其在烟草子叶形成中的作用。
DOI：
10.1007/s00497-007-0058-4
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发表时间：
2007-12-01
影响因子：
--
通讯作者：
Zhao, Jie
中科院分区：
文献类型：
--
作者：
Qin, Yuan;Zhao, Jie
阿拉伯半乳聚糖蛋白（AGPs）参与植物的发育，包括植物的有性生殖。本论文研究了AGPs的表达以及β-葡萄糖基Yariv试剂（β GlcY，其结合阿拉伯半乳聚糖蛋白）在胚胎发育和子叶形成中的作用。免疫荧光分析显示，抗体JIM 13标记的AGPs表达受发育调控。在早期阶段，除了在胚柄基细胞中有一个短的极性表达外，AGPs在整个胚中均匀分布。球形胚时期，胚体、胚体顶端、胚体与胚柄交界处凝聚有AGPs。在心形胚中，APGs仅存在于胚柄与胚外膜的交界处。免疫胶体金标记结果表明，AGPs在胚柄与胚柄交界处的细胞壁中有较强的表达。在离体胚珠培养基中添加β-GlcY可导致胚生长延迟、子叶缺损和脉序模式异常。因此，β GlcY诱导具有变形或不规则的单个子叶的特征的缺陷幼苗死亡。这些结果表明，AGPs在烟草胚胎发育、子叶形成和幼苗形态建成中起着重要作用。
Arabinogalactan proteins (AGPs) have been implicated in plant development including sexual plant reproduction. In this paper, the expression of AGPs and the effects of beta-glucosyl Yariv reagent (beta GlcY, which binds arabinogalactan proteins) in embryo development and cotyledon formation were investigated. Immunofluorescence assay displayed that the expression of AGPs labeled with antibody JIM13 was developmentally regulated. In early stages, AGPs were evenly distributed in the whole embryo, except for a short polar expression in the basal suspensor cell. In the globular stage of embryo, AGPs were condensed in the embryo proper (EP), apex of the EP, and at the juncture of the EP and suspensor. In heart-shaped embryo, APGs were only present at the juncture of the EP and suspensor. Immunogold labeling assay showed that the strong expression of AGPs at the juncture of the EP and suspensor was localized in the cell wall. Provision of beta GlcY to the in vitro ovule culture medium caused delayed growth of embryos, cotyledon defect and abnormal venation pattern. Consequently, beta GlcY induced the death of defective seedlings with the characteristics of deformed or irregular single cotyledon. Our results suggested that AGPs play functional roles in embryo development, cotyledon formation and seedling morphology establishment in Nicotiana tabacum L.