Faculty of Biology, Medicine and Health, University of Manchester, Michael Smith Building, Dover Street, Manchester M13 9PT, UK.
Plant Physiol. 2023 Dec 30;194(1):51-66. doi: 10.1093/plphys/kiad491.
The plant cell wall is a complex and dynamic extracellular matrix. Plant primary cell walls are the first line of defense against pathogens and regulate cell expansion. Specialized cells deposit a secondary cell wall that provides support and permits water transport. The composition and organization of the cell wall varies between cell types and species, contributing to the extensibility, stiffness, and hydrophobicity required for its proper function. Recently, many of the proteins involved in the biosynthesis, maintenance, and remodeling of the cell wall have been identified as being post-translationally modified with lipids. These modifications exhibit diverse structures and attach to proteins at different sites, which defines the specific role played by each lipid modification. The introduction of relatively hydrophobic lipid moieties promotes the interaction of proteins with membranes and can act as sorting signals, allowing targeted delivery to the plasma membrane regions and secretion into the apoplast. Disruption of lipid modification results in aberrant deposition of cell wall components and defective cell wall remodeling in response to stresses, demonstrating the essential nature of these modifications. Although much is known about which proteins bear lipid modifications, many questions remain regarding the contribution of lipid-driven membrane domain localization and lipid heterogeneity to protein function in cell wall metabolism. In this update, we highlight the contribution of lipid modifications to proteins involved in the formation and maintenance of plant cell walls, with a focus on the addition of glycosylphosphatidylinositol anchors, N-myristoylation, prenylation, and S-acylation.
植物细胞壁是一种复杂而动态的细胞外基质。植物初生细胞壁是抵御病原体的第一道防线，调节细胞扩张。特化细胞沉积次生细胞壁，提供支撑并允许水分运输。细胞壁的组成和结构在细胞类型和物种之间有所不同，这有助于其正常功能所需的伸展性、刚性和疏水性。最近，许多参与细胞壁生物合成、维持和重塑的蛋白质已被确定为经过脂质的翻译后修饰。这些修饰具有不同的结构，并在不同的位点附着在蛋白质上，从而定义了每种脂质修饰的特定作用。相对疏水性脂质部分的引入促进了蛋白质与膜的相互作用，并可以作为分选信号，允许靶向递送到质膜区域并分泌到质外体。脂质修饰的破坏导致细胞壁成分的异常沉积和细胞壁重塑对胁迫的反应缺陷，证明了这些修饰的重要性。尽管人们已经了解了哪些蛋白质带有脂质修饰，但关于脂质驱动的膜域定位和脂质异质性对细胞壁代谢中蛋白质功能的贡献仍存在许多问题。在本更新中，我们重点介绍了脂质修饰对参与植物细胞壁形成和维持的蛋白质的贡献，特别是糖基磷脂酰肌醇锚定、N-豆蔻酰化、异戊烯基化和 S-酰化的添加。
