title: Receptor-Like Kinase RUPO Interacts with Potassium Transporters to Regulate Pollen Tube Growth and Integrity in Rice.
abstract: During sexual reproduction of flowering plants, the pollen tube grows fast and over a long distance within the pistil to deliver two sperms for double fertilization. Growing plant cells need to communicate constantly with external stimuli as well as monitor changes in surface tension of the cell wall and plasma membrane to coordinate these signals and internal growth machinery; however, the underlying mechanisms remain largely unknown. Here we show that the rice member of plant-specific receptor-like kinase CrRLK1Ls subfamily, Ruptured Pollen tube (RUPO), is specifically expressed in rice pollen. RUPO localizes to the apical plasma membrane and vesicle of pollen tubes and is required for male gamete transmission. K+ levels were greater in pollen of homozygous CRISPR-knockout lines than wild-type plants, and pollen tubes burst shortly after germination. We reveal the interaction of RUPO with high-affinity potassium transporters. Phosphorylation of RUPO established and dephosphorylation abolished the interaction. These results have revealed the receptor-like kinase as a regulator of high-affinity potassium transporters via phosphorylation-dependent interaction, and demonstrated a novel receptor-like kinase signaling pathway that mediates K+ homeostasis required for pollen tube growth and integrity.
authors.affiliation: Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China.|University of Chinese Academy of Sciences, Beijing, China.
authors.forename: Lingtong
authors.initials: L
authors.lastname: Liu
authors.affiliation: Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China.|University of Chinese Academy of Sciences, Beijing, China.
authors.forename: Canhui
authors.initials: C
authors.lastname: Zheng
authors.affiliation: Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
authors.forename: Baijan
authors.initials: B
authors.lastname: Kuang
authors.affiliation: Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
authors.forename: Liqin
authors.initials: L
authors.lastname: Wei
authors.affiliation: Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
authors.forename: Longfeng
authors.initials: L
authors.lastname: Yan
authors.affiliation: Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
authors.forename: Tai
authors.initials: T
authors.lastname: Wang
mesh_terms: D017360:Arabidopsis / Q000235:genetics; D029681:Arabidopsis Proteins / Q000235:genetics; D035264:Flowers / Q000235:genetics / Q000254:growth & development; D018506:Gene Expression Regulation, Plant; D018525:Germination / Q000235:genetics; D006706:Homeostasis; D019684:Magnoliopsida / Q000235:genetics / Q000254:growth & development; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics*; D012275:Oryza / Q000235:genetics* / Q000254:growth & development; D010766:Phosphorylation; D010940:Plant Proteins / Q000235:genetics*; D011058:Pollen / Q000235:genetics / Q000254:growth & development; D053205:Pollen Tube / Q000235:genetics* / Q000254:growth & development; D054817:Pollination / Q000235:genetics; D027961:Potassium-Hydrogen Antiporters / Q000096:biosynthesis / Q000235:genetics*; D011494:Protein Kinases / Q000235:genetics; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics*
chemical_list: D029681:Arabidopsis Proteins; D008565:Membrane Proteins; D010940:Plant Proteins; D027961:Potassium-Hydrogen Antiporters; C546340:ANXUR1 protein, Arabidopsis; C546341:ANXUR2 protein, Arabidopsis; D011494:Protein Kinases; D020794:Receptor Protein-Tyrosine Kinases