Phosphorylation of the alpha- I motif in SYMRK drives root nodule organogenesis

• 成果类型: Article
• 署名作者: Abel, Nikolaj B.; Norgaard, Malita M. M.; Hansen, Simon B.; Gysel, Kira; Diez, Ignacio Arribas; Jensen, Ole N.; Stougaard, Jens; Andersen, Kasper R.
• 署名单位: Aarhus University; University of Southern Denmark
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-11898
• DOI: 10.1073/pnas.2311522121
• 发表日期: 2024-02-20
• 关键词: receptor kinase; activation; bacterial; complex

摘要

Symbiosis receptor- like kinase SYMRK is required for root nodule symbiosis between legume plants and nitrogen- fixing bacteria. To understand symbiotic signaling from SYMRK, we determined the crystal structure to 1.95 angstrom and mapped the phosphorylation sites onto the intracellular domain. We identified four serine residues in a conserved alpha- I motif, located on the border between the kinase core domain and the flexible C- terminal tail, that, when phosphorylated, drives organogenesis. Substituting the four serines with alanines abolished symbiotic signaling, while substituting them with phosphorylation- mimicking aspartates induced the formation of spontaneous nodules in the absence of bacteria. These findings show that the signaling pathway controlling root nodule organogenesis is mediated by SYMRK phosphorylation, which may help when engineering this trait into non- legume plants.