title: Heterotrimeric G proteins interact with defense-related receptor-like kinases in Arabidopsis.
abstract: Heterotrimeric G proteins (G-proteins) are versatile signaling elements conserved in Eukaryotes. In animals G-proteins relay signals from 7-transmembrane spanning G protein-coupled receptors (GPCRs) to intracellular downstream effectors; however, the existence of GPCRs in plants is controversial. Contrastingly, a surplus of receptor-like kinases (RLKs) provides signal recognition at the plant cell surface. It is established that G proteins are involved in plant defense and suggested that they relay signals from defense-related RLKs. However, it is unclear how the signaling is conducted, as physical interaction between the RLKs and G proteins has not been demonstrated. Using yeast split-ubiquitin system and Bimolecular Fluorescence Complementation assays, we demonstrate physical interaction between the Gα, Gγ1 and Gγ2 subunits, and the defense-related RD-type receptor like kinases CERK1, BAK1 and BIR1. At the same time, no interaction was detected with the non-RD RLK FLS2. We hypothesize that G-proteins mediate signal transduction immediately downstream of the pathogenesis-related RLKs.
authors.affiliation: School of Agriculture and Food Sciences, University of Queensland, Brisbane, QLD 4072, Australia; Current address: Department of Plant Biochemistry, Molecular and Cell Biology, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain.
authors.forename: María Nieves
authors.initials: MN
authors.lastname: Aranda-Sicilia
authors.affiliation: School of Agriculture and Food Sciences, University of Queensland, Brisbane, QLD 4072, Australia.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Trusov
authors.affiliation: School of Agriculture and Food Sciences, University of Queensland, Brisbane, QLD 4072, Australia.
authors.forename: Natsumi
authors.initials: N
authors.lastname: Maruta
authors.affiliation: School of Agriculture and Food Sciences, University of Queensland, Brisbane, QLD 4072, Australia; Current address: Biology Department, Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: David
authors.initials: D
authors.lastname: Chakravorty
authors.affiliation: Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
authors.forename: Yuelin
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: School of Agriculture and Food Sciences, University of Queensland, Brisbane, QLD 4072, Australia. Electronic address: j.botella@uq.edu.au.
authors.forename: José Ramón
authors.initials: JR
authors.lastname: Botella
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D020962:Heterotrimeric GTP-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D029681:Arabidopsis Proteins; D017346:Protein Serine-Threonine Kinases; D020962:Heterotrimeric GTP-Binding Proteins
keywords: Arabidopsis; Heterotrimeric G proteins; Plant defence; Protein–protein interaction; Receptor-like kinases (RLKs)