Xi Lin, Wu Xu Na, Gilbert Max, Schulze Waltraud X
Department of Plant Systems Biology, University of Hohenheim, Stuttgart, Germany.
Front Plant Sci. 2019 Apr 16;10:472. doi: 10.3389/fpls.2019.00472. eCollection 2019.
Receptor kinases (RK) constitute the largest protein kinase family in plants. In particular, members of the leucine-rich repeat-receptor kinases (LRR-RKs) are involved in the perception of various signals at the plasma membrane. Experimental evidence over the past years revealed a conserved activation mechanism through ligand-inducible heterodimer formation: a ligand is recognized by a receptor kinase with a large extracellular domain (ECD). This ligand binding receptor directly interacts with a so-called co-receptor with a small ECD for ligand fixation and kinase activation. A large proportion of LRR-RKs is functionally still uncharacterized and the dynamic complexity of the plasma membrane makes it difficult to precisely define receptor kinase heterodimer pairs and their functions. In this review, we give an overview of the current knowledge of LRR receptor and co-receptor functions. We use ECD lengths to classify the LRR receptor kinase family and describe different interaction properties of ligand-binding receptors and their respective co-receptor from a network perspective.
受体激酶（RK）是植物中最大的蛋白激酶家族。特别是，富含亮氨酸重复序列的受体激酶（LRR-RK）成员参与质膜上各种信号的感知。过去几年的实验证据揭示了一种通过配体诱导的异源二聚体形成的保守激活机制：配体由具有大细胞外结构域（ECD）的受体激酶识别。这种配体结合受体直接与具有小ECD的所谓共受体相互作用，以固定配体并激活激酶。很大一部分LRR-RK在功能上仍未得到表征，质膜的动态复杂性使得难以精确界定受体激酶异源二聚体对及其功能。在这篇综述中，我们概述了LRR受体和共受体功能的当前知识。我们使用ECD长度对LRR受体激酶家族进行分类，并从网络角度描述配体结合受体及其各自共受体的不同相互作用特性。
