The Boron Efflux Transporter ROTTEN EAR Is Required for Maize Inflorescence Development and Fertility
The Boron Efflux Transporter ROTTEN EAR Is Required for Maize Inflorescence Development and Fertility
复制标题
DOI：
10.1105/tpc.114.125963
复制
发表时间：
2014-07-01
期刊：
影响因子：
11.6
通讯作者：
Gallavotti, Andrea
中科院分区：
文献类型：
--
作者：
Chatterjee, Mithu;Tabi, Zara;Gallavotti, Andrea
虽然硼的天然丰度相对较低，但它是一种必需的植物微量营养素。硼缺乏在世界上几个地区造成重大作物损失，影响各种植物物种的繁殖和产量。尽管硼在作物生产中的重要性，但令人惊讶的是，人们对它对生殖器官发育的影响知之甚少。我们分离出一种玉米（Zea mays）突变体，称为烂穗（rte），它在营养和生殖发育方面表现出明显的缺陷，最终导致其花序、雄穗和穗的广泛不育。定位克隆显示，rte编码一个膜定位的硼外排转运蛋白，共同orthopathic拟南芥BOR1蛋白。根据土壤中硼的有效性，rte植物表现出广泛的表型缺陷，可以通过向土壤中补充外源硼酸来完全挽救，这表明rte对硼向气生组织的运输至关重要。RTE在营养组织和生殖组织中的木质部周围的细胞中表达，并且是分生组织活性和器官发育所需的。我们发现，低硼供应的花序的结果在细胞和细胞壁完整性的广泛缺陷，突出硼在形成完全肥沃的生殖器官的结构的重要性。
Although boron has a relatively low natural abundance, it is an essential plant micronutrient. Boron deficiencies cause major crop losses in several areas of the world, affecting reproduction and yield in diverse plant species. Despite the importance of boron in crop productivity, surprisingly little is known about its effects on developing reproductive organs. We isolated a maize (Zea mays) mutant, called rotten ear (rte), that shows distinct defects in vegetative and reproductive development, eventually causing widespread sterility in its inflorescences, the tassel and the ear. Positional cloning revealed that rte encodes a membrane-localized boron efflux transporter, co-orthologous to the Arabidopsis thaliana BOR1 protein. Depending on the availability of boron in the soil, rte plants show a wide range of phenotypic defects that can be fully rescued by supplementing the soil with exogenous boric acid, indicating that rte is crucial for boron transport into aerial tissues. rte is expressed in cells surrounding the xylem in both vegetative and reproductive tissues and is required for meristem activity and organ development. We show that low boron supply to the inflorescences results in widespread defects in cell and cell wall integrity, highlighting the structural importance of boron in the formation of fully fertile reproductive organs.