title: Cell surface ABP1-TMK auxin-sensing complex activates ROP GTPase signaling.
abstract: Auxin-binding protein 1 (ABP1) was discovered nearly 40 years ago and was shown to be essential for plant development and morphogenesis, but its mode of action remains unclear. Here, we report that the plasma membrane-localized transmembrane kinase (TMK) receptor-like kinases interact with ABP1 and transduce auxin signal to activate plasma membrane-associated ROPs [Rho-like guanosine triphosphatases (GTPase) from plants], leading to changes in the cytoskeleton and the shape of leaf pavement cells in Arabidopsis. The interaction between ABP1 and TMK at the cell surface is induced by auxin and requires ABP1 sensing of auxin. These findings show that TMK proteins and ABP1 form a cell surface auxin perception complex that activates ROP signaling pathways, regulating nontranscriptional cytoplasmic responses and associated fundamental processes.
authors.affiliation: Center for Plant Cell Biology, Department of Botany and Plant Sciences, University of California, Riverside, CA 92521, USA.
authors.forename: Tongda
authors.initials: T
authors.lastname: Xu
authors.forename: Ning
authors.initials: N
authors.lastname: Dai
authors.forename: Jisheng
authors.initials: J
authors.lastname: Chen
authors.forename: Shingo
authors.initials: S
authors.lastname: Nagawa
authors.forename: Min
authors.initials: M
authors.lastname: Cao
authors.forename: Hongjiang
authors.initials: H
authors.lastname: Li
authors.forename: Zimin
authors.initials: Z
authors.lastname: Zhou
authors.forename: Xu
authors.initials: X
authors.lastname: Chen
authors.forename: Riet
authors.initials: R
authors.lastname: De Rycke
authors.forename: Hana
authors.initials: H
authors.lastname: Rakusová
authors.forename: Wuyi
authors.initials: W
authors.lastname: Wang
authors.forename: Alan M
authors.initials: AM
authors.lastname: Jones
authors.forename: Jirí
authors.initials: J
authors.lastname: Friml
authors.forename: Sara E
authors.initials: SE
authors.lastname: Patterson
authors.forename: Anthony B
authors.initials: AB
authors.lastname: Bleecker
authors.forename: Zhenbiao
authors.initials: Z
authors.lastname: Yang
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics; D002462:Cell Membrane / Q000201:enzymology*; D007210:Indoleacetic Acids / Q000378:metabolism*; D018515:Plant Leaves / Q000201:enzymology / Q000235:genetics; D010940:Plant Proteins / Q000378:metabolism*; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000378:metabolism*; D015398:Signal Transduction; D020741:rho GTP-Binding Proteins / Q000378:metabolism*
chemical_list: D007210:Indoleacetic Acids; D010940:Plant Proteins; D011956:Receptors, Cell Surface; C083846:auxin-binding protein 1; D011494:Protein Kinases; D020741:rho GTP-Binding Proteins