Molecular mechanisms underlying plant cell death in response to cell wall stress

最近，人们对生产可用作生物燃料原料的可再生资源的高纤维素植物产生了极大的兴趣。纤维素是一种复杂的糖，存在于植物细胞壁中，与半纤维素、果胶和结构蛋白或调节蛋白有关。植物细胞壁形成一种细胞外基质，对保护植物细胞免受环境因素和入侵病原体的侵袭至关重要。植物细胞壁的确切成分和结构在植物生长发育过程中会发生变化，也可以根据各种不利条件进行修改，以确保植物的生长和存活。有趣的是，植物细胞可以逐渐适应由纤维素合成抑制剂引起的细胞壁压力。然而，细胞壁的合成和组织过程中的重要干扰可能会导致细胞死亡。 这项研究将研究植物细胞如何感知那些由纤维素合成减少引起的细胞壁修改。在植物模型拟南芥中，将使用纤维素合成的抑制剂来诱导细胞壁的修饰。我们还将确定这些干扰如何激活细胞修复和补偿机制，或者可能导致细胞死亡。这项研究将为植物细胞对伤害或病原体引起的细胞壁损伤做出反应的机制提供重要的信息。这些信息也可能有助于优化生物能源作物及其用于工业加工的细胞壁。

Recently, a lot of interest has focused on the production of plants with high cellulose content that could be used as renewable source of biofuel feed stock. Cellulose is a complex sugar found in plant cell walls, where it is associated with hemicellulose, pectins and structural or regulatory proteins. Plant cell walls form an extracellular matrix essential to protect plant cells from environmental factors and invading pathogens. The exact composition and structure of plant cell walls change during plant growth and development and can also be modified in response to various adverse conditions to ensure plant growth and survival. Interestingly, plant cells can progressively be adapted to cell wall stress caused by inhibitors of cellulose synthesis. Nonetheless, important perturbations in the synthesis and organisation of the cell wall may lead to cell death. This research will study how cell wall modifications such as those caused by reduced cellulose synthesis are perceived by plant cells. Cell wall modifications will be induced in the plant model Arabidopsis thaliana using inhibitors of cellulose synthesis. We will also determine how these perturbations can activate cell repair and compensatory mechanisms or may lead to cell death. This study will bring important information on the mechanisms used by plant cells to respond to cell wall damage as induced by wounding or pathogens. This information may also be useful for the optimization of bioenergy crops and their cell walls for industrial processing.