signal transduction; peptide hormones; kinase signalling; protein crystallography; plant development; membrane receptor kinases; Arabidopsis genetics; plant biochemistry
Anne Pauline, Amiguet-Vercher Amelia, Brandt Benjamin, Kalmbach Lothar, Geldner Niko, Hothorn Michael, Hardtke Christian S. (2018), CLERK is a novel receptor kinase required for sensing of root-active CLE peptides in Arabidopsis, in Development
, 145(10), dev162354-dev162354.
Hazak Ora, Brandt Benjamin, Cattaneo Pietro, Santiago Julia, Rodriguez?Villalon Antia, Hothorn Michael, Hardtke Christian S (2017), Perception of root-active CLE peptides requires CORYNE function in the phloem vasculature, in EMBO reports
Hohmann Ulrich, Lau Kelvin, Hothorn Michael (2017), The Structural Basis of Ligand Perception and Signal Activation by Receptor Kinases, in Annual Review of Plant Biology
, 68(1), 109-137.
Santiago Julia, Brandt Benjamin, Wildhagen Marie, Hohmann Ulrich, Hothorn Ludwig Alfred, Butenko Melinka, Hothorn Michael (2016), Mechanistic insight into a peptide hormone signaling complex mediating floral organ abscission, in eLife
, 5( pii: e150), 1-19.
Plants are nature's other successful experiment with multicellular life. Just like animals, plants use peptide hormones to integrate their growth and development, the formation of tissues and organs and the maintenance of stem cell populations. Diverse plant peptide hormones are sensed by leucine-rich repeat (LRR) receptor kinases, a plant-unique family of membrane signaling proteins. Several receptor-ligand pairs have been genetically identified, but it is presently unknown how LRR kinases specifically sense different peptide hormones, how they transduce the signal across the plasma membrane or how they activate cytoplasmic signaling cascades. Here we propose to dissect how two distinct peptide signaling systems operate at the molecular level: The LRR receptor kinase HAESA senses a family of IDA peptide hormones to regulate floral abscission. We have identified the active form of IDA, which unexpectedly turns out to be structurally related to CLE peptide hormones. CLEs and their CLAVATA/BAM receptors control stem cell populations in the root and in the shoot. We will combine quantitative biochemistry and X-ray crystallography with cell biology and reverse genetics in Arabidopsis, to study in molecular detail how IDA and CLE peptides specifically bind their receptors and how these receptors become activated through recruitment of co-receptor helper proteins. Our work may uncover a common receptor activation mechanism for diverse plant peptide hormones and aid the design of potent receptor agonists and antagonists with applications in the lab and in the field.