Polarized cell growth in Arabidopsis requires endosomal recycling mediated by GBF1-related ARF exchange factors
Polarized cell growth in Arabidopsis requires endosomal recycling mediated by GBF1-related ARF exchange factors
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DOI：
10.1038/ncb2389
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发表时间：
2012-01-01
影响因子：
21.3
通讯作者：
Juergens, Gerd
中科院分区：
文献类型：
--
作者：
Richter, Sandra;Mueller, Lena M.;Juergens, Gerd
极化尖端生长是许多真核生物中的基本细胞过程，介导神经元轴突和树突（1）或真菌菌丝（2）的生长。在植物中，花粉和根毛是分析顶端生长的细胞模型系统（3-5）。细胞生长依赖于膜运输。这种膜交通的调节在很大程度上是未知的尖端生长的细胞，相反，细胞表现出夹层生长。在这里，我们表明，在拟南芥中，GBF 1相关的交换因子ARF GTP酶（ARF GEFs）的GNOME和GNL 2发挥重要作用极尖生长的根毛和花粉，分别。当从相同的启动子表达时，GNL 2（与早期分泌的ARF GEF GNL 1相反）能够在生长素流出调节因子PIN 1从内体到非尖端生长细胞中的基底质膜的极性再循环中取代GNOME。因此，极性循环促进极尖生长，GNL 2似乎已经进化到满足高等植物快速生长花粉的特定要求。
Polarized tip growth is a fundamental cellular process in many eukaryotic organisms, mediating growth of neuronal axons and dendrites(1) or fungal hyphae(2). In plants, pollen and root hairs are cellular model systems for analysing tip growth(3-5). Cell growth depends on membrane traffic. The regulation of this membrane traffic is largely unknown for tip-growing cells, in contrast to cells exhibiting intercalary growth. Here we show that in Arabidopsis, GBF1-related exchange factors for the ARF GTPases (ARF GEFs) GNOM and GNL2 play essential roles in polar tip growth of root hairs and pollen, respectively. When expressed from the same promoter, GNL2 (incontrast to the early-secretory ARF GEF GNL1) is able to replace GNOM in polar recycling of the auxin efflux regulator PIN1 from endosomes to the basal plasma membrane in non-tip growing cells. Thus, polar recycling facilitates polar tip growth, and GNL2 seems to have evolved to meet the specific requirement of fast-growing pollen in higher plants.