Laboratory of Plant Stress Ecophysiology and Biotechnology, Cold and Arid Regions Environmental and Engineering Institute, Chinese Academy of Sciences, Lanzhou, China.
Plant Signal Behav. 2011 Sep;6(9):1297-9. doi: 10.4161/psb.6.9.17507.
The plant cuticle, a cutin matrix embedded with and covered by wax, seals the aerial organ's surface to protect the plant against uncontrolled water loss. The cutin matrix is essential for the cuticle to function as a barrier to water loss. Recently, we identified from wild barley a drought supersensitive mutant, eibi1, which is caused by a defective cutin matrix as the result of the loss of function of HvABCG31, an ABCG full transporter. Here, we report that eibi1 epidermal cells contain lipid-like droplets, which are supposed to consist of cutin monomers that have not been transported out of the cells. The eibi1 cuticle is fragile due to a defective cutin matrix. The rice ortholog of the EIBI1 gene has a similar pattern of expression, young shoot but not flag leaf blade, as the barley gene. The model of the function of Eibi1 is discussed. The HvABCG31 full transporter functions in the export of cutin components and contributed to land plant colonization, hence also to terrestrial life evolution.
植物表皮，一种被蜡嵌入和覆盖的角质基质，将气生器官的表面密封起来，以防止植物不受控制地失水。角质基质对于角质层作为水分流失的屏障功能至关重要。最近，我们从野生大麦中鉴定出一个干旱超敏突变体 eibi1，它是由于 HvABCG31 的功能丧失导致角质基质缺陷引起的，HvABCG31 是一个 ABCG 全转运蛋白。在这里，我们报告 eibi1 表皮细胞含有类脂样液滴，这些液滴应该由尚未从细胞中运出的角质单体组成。由于角质基质缺陷，eibi1 表皮脆弱。EIBI1 基因的水稻同源基因在表达模式上与大麦基因相似，只在幼茎中表达，而不在旗叶叶片中表达。讨论了 Eibi1 的功能模型。HvABCG31 全转运蛋白在角质成分的输出中发挥作用，有助于陆地植物的定殖，从而也有助于陆地生命的进化。
