Involvement of RTE1 in conformational changes promoting ETR1 ethylene receptor signaling in Arabidopsis.
Ethylene is an important regulator of plant growth, development and responses to environmental stresses. Arabidopsis perceives ethylene through five homologous receptors that negatively regulate ethylene responses. RTE1, a novel gene conserved in plants, animals and some protists, was recently identified as a positive regulator of the ETR1 ethylene receptor. Here, we genetically analyze the dependence of ETR1 on RTE1 in order to obtain further insight into RTE1 function. The function of RTE1 was found to be independent and distinct from that of RAN1, which encodes a copper transporter required for ethylene receptor function. We tested the ability of an rte1 loss-of-function mutation to suppress 11 etr1 ethylene-binding domain mis-sense mutations, all of which result in dominant ethylene insensitivity due to constitutive signaling. This suppression test uncovered two classes of etr1 mutations -RTE1-dependent and RTE1-independent. The nature of these mutations suggests that the ethylene-binding domain is a possible target of RTE1 action. Based on these findings, we propose that RTE1 promotes ETR1 signaling through a conformational effect on the ethylene-binding domain.
Resnick
Josephine S
JS
Department of Cell Biology and Molecular Genetics, Bioscience Research Building, University of Maryland, College Park, MD 20742-5815, USA.
Rivarola
Maximo
M
Chang
Caren
C
D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D027682:Cation Transport Proteins / Q000235:genetics / Q000378:metabolism; D000079922:Copper Transport Proteins; D005030:Ethylenes / Q000378:metabolism* / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D005838:Genotype; D008565:Membrane Proteins / Q000378:metabolism*; D009154:Mutation; D010641:Phenotype; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D011487:Protein Conformation; D016601:RNA-Binding Proteins; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D019076:Transgenes; D020931:ran GTP-Binding Protein
D029681:Arabidopsis Proteins; C490178:At5g20010 protein, Arabidopsis; D027682:Cation Transport Proteins; D000079922:Copper Transport Proteins; C494590:ETR1 protein, Arabidopsis; D005030:Ethylenes; D008565:Membrane Proteins; D016601:RNA-Binding Proteins; C525374:RTE1 protein, Arabidopsis; D011956:Receptors, Cell Surface; C036216:ethylene; D020931:ran GTP-Binding Protein