Title: | "The bacterial volatile N,N-dimethyl-hexadecylamine promotes Arabidopsis primary root elongation through cytokinin signaling and the AHK2 receptor" |
Author(s): | Vazquez-Chimalhua E; Barrera-Ortiz S; Valencia-Cantero E; Lopez-Bucio J; Ruiz-Herrera LF; |
Address: | "Instituto de Investigaciones Quimico-Biologicas, Universidad Michoacana de San Nicolas de Hidalgo. Edificio B3, Ciudad Universitaria, Morelia, Michoacan, Mexico" |
DOI: | 10.1080/15592324.2021.1879542 |
ISSN/ISBN: | 1559-2324 (Electronic) 1559-2316 (Print) 1559-2316 (Linking) |
Abstract: | "N,N-dimethyl-hexadecylamine (DMHDA) is a volatile organic compound (VOC) produced by some plant growth-promoting rhizobacteria (PGPR), which inhibits the growth of pathogenic fungi and induces iron uptake by roots. In this report, through the application of a wide range of concentrations, we found that DMHDA affects Arabidopsis primary root growth and lateral root formation in a dose-dependent manner where 1 and 2 microM promoted root growth and higher (4-32 microM) concentrations repressed growth. Cytokinin-inducible TCS::GFP and ARR5::uidA gene constructs showed an increased expression in columella cells and root meristem, respectively, at 2 microM DMHDA, but their expression domains strongly diminished at growth repressing treatments. To test if either primary root growth promotion or repression could involve members of the cytokinin receptor family, the growth of WT and double mutant combinations cre1-12 ahk2-2, cre1-12 ahk3-3, and ahk2-2 ahk3-3 was tested in control conditions or supplemented with 2 microM or 16 microM DMHDA. Noteworthy, the root growth promotion disappeared in cre1-12 ahk2-2 and ahk2-2 ahk3-3 combinations, whereas all double mutants had higher repression than the WT at high doses. We further show that DMHDA fails to mimic the effects of ethylene in Arabidopsis seedlings grown in darkness that include an exaggerated apical hook, stem and root shortening, and root hair elongation. Our data help unravel how Arabidopsis senses a growth-modulating bacterial volatile through changes in cytokinin responsiveness" |
Keywords: | "Arabidopsis/drug effects/genetics/growth & development/*metabolism Arabidopsis Proteins/genetics/*metabolism Cytokinins/*metabolism Gene Expression Regulation, Plant/drug effects Genes, Reporter Histidine Kinase/genetics/*metabolism Methylamines/*pharmaco;" |
Notes: | "MedlineVazquez-Chimalhua, Ernesto Barrera-Ortiz, Salvador Valencia-Cantero, Eduardo Lopez-Bucio, Jose Ruiz-Herrera, Leon Francisco eng Research Support, Non-U.S. Gov't 2021/02/16 Plant Signal Behav. 2021 Apr 3; 16(4):1879542. doi: 10.1080/15592324.2021.1879542. Epub 2021 Feb 15" |