Abstract:
Plant receptor kinases are key transducers of extracellular stimuli, such as the presence of beneficial or pathogenic microbes or secreted signaling molecules. Receptor kinases are regulated by numerous post-translational modifications.1,2,3 Here, using the immune receptor kinases FLS24 and EFR,5 we show that S-acylation at a cysteine conserved in all plant receptor kinases is crucial for function. S-acylation involves the addition of long-chain fatty acids to cysteine residues within proteins, altering their biochemical properties and behavior within the membrane environment.6 We observe S-acylation of FLS2 at C-terminal kinase domain cysteine residues within minutes following the perception of its ligand, flg22, in a BAK1 co-receptor and PUB12/13 ubiquitin ligase-dependent manner. We demonstrate that S-acylation is essential for FLS2-mediated immune signaling and resistance to bacterial infection. Similarly, mutating the corresponding conserved cysteine residue in EFR suppressed elf18-triggered signaling. Analysis of unstimulated and activated FLS2-containing complexes using microscopy, detergents, and native membrane DIBMA nanodiscs indicates that S-acylation stabilizes, and promotes retention of, activated receptor kinase complexes at the plasma membrane to increase signaling efficiency.
摘要:
植物受体激酶是细胞外刺激的关键传感器,例如存在有益的或致病的微生物或分泌的信号分子。受体激酶受许多翻译后修饰的调节。1,2,3此处,使用免疫受体激酶FLS24和EFR,在图5中,我们显示在所有植物受体激酶中保守的半胱氨酸处的S-酰化对于功能是至关重要的。S-酰化涉及将长链脂肪酸添加到蛋白质中的半胱氨酸残基,在膜环境中改变其生化特性和行为.6我们在感知其配体后的几分钟内观察到FLS2在C末端激酶结构域半胱氨酸残基处的S-酰化,flg22,以BAK1共受体和PUB12/13泛素连接酶依赖性方式。我们证明了S-酰化对于FLS2介导的免疫信号传导和对细菌感染的抗性是必不可少的。同样,EFR中相应保守半胱氨酸残基的突变抑制了elf18触发的信号传导。使用显微镜分析未刺激和激活的含FLS2的复合物,洗涤剂,和天然膜DIBMA纳米盘表明S-酰化稳定,并促进保留,激活质膜上的受体激酶复合物以增加信号传导效率。