Sequence adaptation of Symbiosis Receptor-like Kinase (SymRK) enabling nitrogen-fixing root nodule development

共生受体样激酶 (SymRK) 的序列适应促进固氮根瘤发育

• 批准号: 469056651
• 负责人: Professor Dr. Martin Parniske
• 金额: --
• 依托单位: Institut für Genetik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2021
• 资助国家: 德国
• 起止时间: 2020-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/469056651?language=en
• 关键词: Sequence; adaptation; Symbiosis; Receptor; like

Molecular innovations underlying the evolution of novel traits are the drivers of biological diversification. The identification of these drivers provides the milestones within a roadmap to synthetically install or optimize this trait. Fossils of the earliest land plants carry structures of arbuscular mycorrhiza (AM), a symbiosis with nutrient-delivering fungi that most present day land plants still engage in. In contrast, the root nodule symbiosis (RNS) with nitrogen-fixing bacteria is much younger, and restricted to a single phylum comprising four orders of plants, the Fabales, Fagales, Cucurbitales and Rosales. The genetic toolkit underlying the intracellular accommodation of AM fungi is largely conserved across land plants. Parts of it have been co-opted during the evolution of RNS, including a set of signal transduction components such as the Symbiosis Receptor-like Kinase (SymRK). We obtained evidence that during evolution, SymRK underwent super-functionalization; it acquired novel molecular features that facilitated the development of RNS, while maintaining its conserved function for AM. In this project, we will explore the amino acid sequence diversity among SymRK orthologs with the goal to identify critical sequence adaptations that underlie the rhizobial infection of plant cells. We will study the mechanistic consequences of these sequence variations at the cellular and molecular level with a special focus on the SymRK protein interactome. Unravelling protein-protein interactions modulated by these adaptations will pinpoint the specific mechanistic innovations facilitating the symbiotic infection process of plant cells by nitrogen-fixing bacteria.

新特征进化背后的分子创新是生物多样化的驱动力。这些驱动程序的识别提供了综合安装或优化此特征的路线图中的里程碑。最早的陆地植物的化石具有丛枝菌根（AM）的结构，这是一种与营养输送真菌的共生，大多数陆地植物仍在参与这种共生。相比之下，与固氮细菌的根瘤共生（RNS）要年轻得多，并仅限于由四个植物目组成的单一门，即蚕豆目、蚕豆目、葫芦目和蔷薇目。 AM 真菌细胞内调节的遗传工具包在陆地植物中很大程度上是保守的。它的一部分在 RNS 的进化过程中被增补，包括一组信号转导组件，例如共生受体样激酶 (SymRK)。我们获得的证据表明，在进化过程中，SymRK 经历了超功能化；它获得了新的分子特征，促进了 RNS 的发展，同时保持了 AM 的保守功能。在这个项目中，我们将探索 SymRK 直向同源物之间的氨基酸序列多样性，目的是识别植物细胞根瘤菌感染的关键序列适应性。我们将在细胞和分子水平上研究这些序列变异的机制后果，特别关注 SymRK 蛋白相互作用组。解开这些适应调节的蛋白质-蛋白质相互作用将查明促进固氮细菌对植物细胞共生感染过程的具体机制创新。