Uclacyanin proteins are required for lignified nanodomain formation within Casparian strips
Uclacyanin proteins are required for lignified nanodomain formation within Casparian strips
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凯氏带内木质化纳米结构域的形成需要 Uclacyin 蛋白
DOI：
10.1101/2020.05.01.071738
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Reyt G
中科院分区：
文献类型：
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作者：
Reyt G
凯氏带（CS）是维管植物的细胞壁修饰，限制细胞外自由扩散进出维管系统[1]。这种屏障在控制植物正常发育所需的营养和水分的获得方面起着关键作用[2-5]。CS是通过跨越相邻内胚层细胞之间的质外体空间的约2 μm宽和150 nm厚的木质素带的精确沉积形成的[6，7]。在这里，我们确定了一个含铜蛋白，Uclacyanin 1（UCC 1），这是亚区室内CS。UCC 1形成一个中央CS纳米结构域相比，其他CS定位的蛋白质，发现主要是在CS的周边积累。我们发现，两个uclacyanins（UCC 1和UCC 2）的功能丧失减少木质化，特别是在这个中央CS nanodomain，揭示了一个nano-compartmentalized机制的木质素聚合。这种木质化的丧失导致内胚层渗透性增加，从而导致矿物质营养稳态的丧失。
Casparian strips (CSs) are cell wall modifications of vascular plants restricting extracellular free diffusion into and out of the vascular system [1]. This barrier plays a critical role in controlling the acquisition of nutrients and water necessary for normal plant development [2–5]. CSs are formed by the precise deposition of a band of lignin approximately 2 μm wide and 150 nm thick spanning the apoplastic space between adjacent endodermal cells [6, 7]. Here, we identified a copper-containing protein, Uclacyanin1 (UCC1), that is sub-compartmentalized within the CS. UCC1 forms a central CS nanodomain in comparison with other CS-located proteins that are found to be mainly accumulated at the periphery of the CS. We found that loss-of-function of two uclacyanins (UCC1andUCC2) reduces lignification specifically in this central CS nanodomain, revealing a nano-compartmentalized machinery for lignin polymerization. This loss of lignification leads to increased endodermal permeability and, consequently, to a loss of mineral nutrient homeostasis.