Stem cell signaling in Arabidopsis requires CRN to localize CLV2 to the plasma membrane.
Stem cell number in shoot and floral meristems of Arabidopsis (Arabidopsis thaliana) is regulated by the CLAVATA3 (CLV3) signaling pathway. Perception of the CLV3 peptide requires the receptor kinase CLV1, the receptor-like protein CLV2, and the kinase CORYNE (CRN). Genetic analysis suggested that CLV2 and CRN act together and in parallel with CLV1. We studied the intracellular localization of receptor fusions with fluorescent protein tags and their capacities for interaction via efficiency of fluorescence resonance energy transfer. We found that CLV2 and CRN require each other for export from the endoplasmic reticulum and localization to the plasma membrane (PM). CRN readily forms homomers and interacts with CLV2 through the transmembrane domain and adjacent juxtamembrane sequences. CLV1 forms homomers independently of CLV2 and CRN at the PM. We propose that the CLV3 signal is perceived by a tetrameric CLV2/CRN complex and a CLV1 homodimer that localize to the PM and can interact via CRN.
Bleckmann
Andrea
A
Institut für Genetik, Heinrich-Heine Universität Düsseldorf, 40225 Duesseldorf, Germany.
Weidtkamp-Peters
Stefanie
S
Seidel
Claus A M
CA
Simon
Rüdiger
R
D017360:Arabidopsis / Q000166:cytology* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000378:metabolism; D031541:Fluorescence Resonance Energy Transfer; D018506:Gene Expression Regulation, Plant / Q000502:physiology*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D018519:Meristem / Q000378:metabolism; D009154:Mutation; D030821:Plants, Genetically Modified; D017346:Protein Serine-Threonine Kinases; D021381:Protein Transport / Q000502:physiology; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D011956:Receptors, Cell Surface; D013234:Stem Cells / Q000166:cytology / Q000502:physiology*; D014026:Nicotiana / Q000235:genetics / Q000378:metabolism
D029681:Arabidopsis Proteins; C401621:CLV2 protein, Arabidopsis; D008565:Membrane Proteins; D011956:Receptors, Cell Surface; D020794:Receptor Protein-Tyrosine Kinases; C548152:CORYNE protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases